For those products or services which everyone can easily get for themselves, there is no cost (no price) because there is no need to ration nor to pay for someone's time or effort to produce or distribute the product or service.  In a sense when you purchase a product, you are often actually paying for the labor and time (and lifestyle living expenses) of someone else to make it or otherwise acquire and get it to you. In some cases, of course, people may charge extremely high amounts for things that cost them very little labor (e.g., coming across an antique in their basement or a rare and valuable baseball card), but for the most part when you buy a typical product you are paying for the labor (plus profit) that went into its manufacture and distribution.  If lamps just "grew on trees everywhere", one would normally not need to pay for them.

Unfortunately theory does not always conform to practice, since what can be mass produced, or what is in demand by wealthy people (or people who pool their wealth as in insurance plans, investment banking, etc), can make more money than products or services which cannot be mass produced and cannot find willing wealthy patrons (or collectively willing and wealthy patrons in the form of insurance companies, investors, etc.).  Moreover, what is in demand and is profitable may not be good for society, as in cigarettes, unhealthy junk food, low level, mindless forms of entertainment, etc. 

There is, depending on how you look at it, either freedom or the illusion of freedom in the free market mechanism. Freedom and the illusion of freedom are important because they give people a sense of control or autonomy or choice in what they do and what they earn and purchase. And that tends to be a motivating factor in working and in making purchases with one's earnings.  And it takes (other people's) personal judgment out of the matter of deciding who is worthy to receive goods and services, thus tending to minimize hostility over how social benefits are distributed within the economic system. 

That hostility occurs instead in the political realm in political battles between those on the one hand who want to redistribute benefits from the economic system, through taxation and expenditures, in a way different from the way the economic system itself distributes them, and those on the other hand who think particular redistribution plans (or any redistribution plan) are unfair or unwise because they tamper with the incentives and objective, automatic mechanisms of the economic system.  Theoretically it is supply and demand and competition that sets prices, not the autocratic determination by any specific individual or small group of what others ought to consider valuable.  So the mechanism gives the appearance of being objective, mechanical, automatic, and taking into account the desires of individuals.  And while that is partially true, or true in many cases, there are notable conscious and unconscious forces and mechanisms at work that prevent the market as being as responsive as it might be and that make prices, opportunities for making contributions, and opportunities for earning money not as automatic, objective, or free as they are supposed to be or as they sometimes appear to be.

The question is always whether there is any way to change either the system or people's psychological impulses within it (through education or justifiable cultivation) to improve it rather than to harm it.  Much of what occurs within a free market system is based on people's psychology in the sense of what they wish to purchase (fashions change in everything from clothes to food or diet fads), what sort of work they want to do, how much they want to charge for their work if they have any choice at all in pricing their labor, especially if they want to price it for less than the market will bear.  For example, I personally believe that the more important something is, the more it should be available, which means in some cases charging much less for it than one could get, or in some cases giving it away. To some extent that is the opposite principle under which the system usually operates, whereby the more important something is to others, the more money providers will charge, though it has not always been that way.  But to me, charging more for necessities that do not necessarily cost that much to produce, is tantamount, or very close to, gouging, which is normally a reprehensible practice. 

Moreover, it is not necessary to make a profit on necessities if a profit can be made on conveniences or luxuries, so while markets overall need to produce financial profits to sustain and promote further trade, not every item in a market needs to produce a profit, just as not everyone in a corporation needs to be a salesperson or part of a manufacturing assembly line in order to contribute to the overall success and financial profitability of the company.

I also personally think I should charge nice people less (when I can) than people who are not as nice.  Similarly with people who are deserving in some other way -- for example helping a prodigy acquire the tools and education to develop his/her talent to the fullest.  It should not, it seems to me, be the wealthy collector who has the Stradivarius or Guarneri violin, but the person who can play it the best and do the most with it to create the most musical pleasure for people. Supply and affordable demand are not the only way to set prices or distribute products and labor.

Charging less for necessities or giving things away to those who deserve it because of talent are possible within the free market system (not just as a charitable extra), but only if people see the system as working to allow each person to make the best contribution while earning a decent living and, in some sense, a living that is commensurate to the contribution, where that is reasonable and fair, instead of seeing the system either as being there to bring them the most personal benefit, or as automatically working in such a way that the more money they make the more good they must be doing.  If one is working or living by oneself alone on the prairie or in the forest, one has responsibilities only to oneself, but if one is part of an economic community and part of a civil community that is intertwined with the economic system, then one, it seems, acquires mutual responsibilities with others in that community.  How much and what those responsibilities are is a complex matter, dependent upon many factors, but the nature of living in a community seems to entail at least some responsibility to lend an unremunerated hand where it is deserved, necessary, and possible.  There are many benefits to community living that are not simply traded equally in reciprocal transactions, and just as one tends to receive unaccounted benefits from some people, one should be prepared to bestow them on to others, especially when one cannot do something in return for the people who helped them.  Particularly if you cannot pay back someone's beneficence to you, you can pass it on to others.

Of course, one can charge the maximum the market will bear (or price one's goods and services optimally to make the most total revenue) and then give to charity if one wants to make a contribution over and above the products or services one provides in one's career.  Many people do that, sometimes making a fanfare out of their contributions for self-aggrandizement or as free publicity to increase business. Instead they might have charged less to some or to all and made their additional charitable social contribution that way.  There are many ways, within the free market system, to make a contribution, over and above simply doing whatever it takes to make the most money.  And, in many cases, making the most money, even if one gives substantial amounts of it to charity, does not mean one made the greatest possible contribution anyway.

Intellectual property needs skill and usually time to create, but once that creation is done, in the age of information, particularly digital information, typically (and increasingly) the distribution costs are extremely low.  And since ideas are easy to copy, and take far less time to copy than to create in the first place, "pirates of intellectual property" can price their items to make a profit without having to include the creativity labor costs (which are basically the cost of living expenses necessary during the period of time it takes to discover or invent and perfect the idea). The trick is to balance distribution costs to pay production costs and reasonable profit. Copyright, as it stands, does not do that for three reasons: (1) black markets make piracy profitable, (2) piracy is difficult to prevent, and (3) when enforcement of copyright does succeed, it allows, and thus sometimes permits, excessive profit by allowing monopolistic or unfair (gouging) pricing based on essentially an artificial shortage or something akin to hoarding or extortion.  Mechanisms are needed to make neither piracy nor legal "monopolistic" gouging an attractive option, while letting as many people as possible benefit from the relatively inexpensive distribution of intellectual property (that is, inventions, discoveries, art, etc.)  Creativity should be able to be profitable but not, through artificial barriers, at the expense of distribution and availability.

Inflation and deflation cause differential problems for those sorts of financial arrangements which are independent of current price values for products or services. Fixed (retirement or annuity) incomes, loan repayments, foreign monetary exchange, or any other financial transactions based on numerical amount of money alone, rather than on what that numerical amount of money will purchase in the current market are such independent financial transactions.  For example, a $100,000 loan paid back at an interest rate lower than inflation will not purchase as much for the lender as it would have at the time he made the loan.  It works out well for the borrower, but not the lender.  Similarly, if one retires on a fixed income, as inflation grows the money buys less and less, and is less a reflection of the actual contribution one made to the economy when one was working and productive.  For example, baseball stars of 50 years ago may have helped make the game into the valuable commodity it is today, but may only accrue from it a quantity of money based on their incomes at the time, not on how much they helped the game grow to earn.  In some ways this is not much different from an actor's choosing to receive a particular fee for a film performance rather than a percentage of the income, when the film then turns out to be a financial success in part because of his performance.  His income is not commensurate with his contribution in such a case.

But for ongoing trading purposes, inflation and deflation, based on an essentially equally distributed increased or decreased money supply, change prices without changing value because as one has more money, one has to spend that proportion more of it in price increases for the same thing.  If a dozen eggs gives the seller one dollar profit and it takes the sale of 10,000 dozen to buy a car, you are in the same position selling eggs vis-a-vis buying a car, as you are if a dozen eggs yields fifty cents profit, and a car is $5000.  You still have to sell 10,000 dozen to buy a car. The relationship between the value of labor of the egg producer and the value of the automobile manufacture's labor does not change in regard to each other, even though the prices they each charge might.

Of course, inflation, in the sense of equal distribution of increased money supply equally spread around, and prices all rising in the same proportion because of it, seldom happens.  Instead prices might rise in a particular sector of the economy for some reason, and then only those who sell necessities or otherwise in-demand items can increase their prices commensurately.  There is typically a lag in price increases in those sectors that are marginally in demand or that are most dispensable, if they can ever catch up at all. 

It is also usually said that inflation will occur with an increased money supply in an economy that is at full capacity, but even at full capacity there can be shifts in fashion. So additional money in the hands of some people might cause a shift in what is produced rather than just increasing prices for what already is being produced.  Moreover, it is not always clear what "full capacity" or "an economy" means, especially in a supposed global economy, but even in local economies where people, are either underemployed in terms of the quality of what they could be doing, or where people could increase their working hours if they wished to.  And very few, if any economic systems, of any size appear to be at full capacity, other than perhaps in times of dire or all-out war, where every possible amount of "extra" labor is directed toward the war effort.

But the point is that it is not the amount of money in circulation that necessarily causes either inflation or individual sector price rises. Pricing serves different purposes, has multiple functions, and is not just the automatic cause and effect that might be characterized by the application of formulas to products and labor.