> I can't think of a community problem where a market-based solution even helped, let alone solved the problem.

While I agree that the market isn't the panacea and God it's portrayed to be, I didn't understand the GP that way.

Your point goes much too far the other way. Most of most community problems are solved by 'free' markets, including food (most food is bought and sold in the market), much of transportation (cars, planes), shelter (most homes are owned by private parties), etc.

I think the interesting question is, where is the market good at, and what are other tools good at?