LogFAQs > #889266963

From the article:

As this new self-portrait emerges, one surprising trait is worth noting: when we put a monetary value on things that we give a moral value, we can put them in jeopardy. Pay school children to read books and they will, but they may lose the love of reading in the process. Pay farmers to protect the local forest and they will, but their motivation for doing so may switch from respect for the living world to regard for the bottom line. "The market is an instrument, but not an innocent one," warns the Harvard philosopher Michael Sandel, "...sometimes, market values crowd out nonmarket norms worth caring about".

Because, you've instantly turned those things into jobs now.
Even that is basic economics. A kid simply values a small pizza more than the time it takes him to read a book. Pizza Hut values the fake good-will (and the money they get from parents who are likely to buy another pizza) more than it does that small pizza.