People have strong anti-market biases. It has been said that if there was not a market in sandwiches, and one was suggested, people would recoil in horror. "Only the rich will be able to buy sandwiches." "Sandwiches will be filled with rat poison and feces." "It's just wrong! People should feed each other out of kindness, not greed." Even "Many people only sell sandwiches because they need money. It's exploitation."

Taboo tradeoffs. Probably most readers are too young (as am I) to remember when life insurance was considered immoral. How can you put a price on life?

Political incentives. Why should any one voter demand change? Why should any one politician? Or any one judge? Collective action problems are hard.