A very good article by philosopher Michael Sandel for The Atlantic.
Why worry that we are moving toward a society in which everything is up for sale?
For two reasons. One is about inequality, the other about corruption. First, consider inequality. In a society where everything is for sale, life is harder for those of modest means. The more money can buy, the more affluence—or the lack of it—matters. If the only advantage of affluence were the ability to afford yachts, sports cars, and fancy vacations, inequalities of income and wealth would matter less than they do today. But as money comes to buy more and more, the distribution of income and wealth looms larger. The second reason we should hesitate to put everything up for sale is more difficult to describe. It is not about inequality and fairness but about the corrosive tendency of markets. Putting a price on the good things in life can corrupt them. That’s because markets don’t only allocate goods; they express and promote certain attitudes toward the goods being exchanged. Paying kids to read books might get them to read more, but might also teach them to regard reading as a chore rather than a source of intrinsic satisfaction. Hiring foreign mercenaries to fight our wars might spare the lives of our citizens, but might also corrupt the meaning of citizenship.