Lol, I cooperated because $60 was not a large enough sum of money for me to really care about trying to win it, and in the calibration I assumed most people would feel similarly. Reading your reasoning here, however, it is possible I should have accounted more strongly for people who like to win just for the sake of winning, a group that may be larger here than in the general population :p.

Edit: actually that's not really what I mean. I mean people who want to make a rational choice to maximum the probability of winning for its own sake, even if they don't actually care about the prize. I prefer someone gets $60 and is pleasantly surprised to have won, than I get $1. I predict that overall happiness is increased more this way, at negligible cost to myself. Even if the person who wins defected.