Especially from an artificial game theoretic perspective. Real life observations of human beings consistently show higher levels of cooperation than rational choice theory predicts alone. You are taking for granted the vast amount of cooperation and trust that goes into your society. It's so seamless that nobody notices it. People notice competition because it's more obvious when people are in conflict than when they are in harmony.
I used the modifier even, because I can trivially fabricate a game where cooperation yields a negative outcome for both (or all) players -- so I was discounting those kinds of games. Real life and games based on real life tend to be less artificial, but your point is well-taken.
