Humans are not rational. People pay money to have pictures of their kids - this is completely irrational, but we would all agree that someone who doesn't have pictures of their kids is lacking sanity. People pay a lot of money for clothing that is in style when something cheaper would be just as good - sometimes better.

Irrational actors are only punished when their irrationality exceeds a threshold, which is rare in these days where we don't let people starve to death easily.