If noncompetes are such a bad idea, why are they so common? It could be a Prisoner's Dilemma where everyone's defecting (a similar situation to hockey players

If noncompetes are such a bad idea, why are they so common? It could be a Prisoner's Dilemma where everyone's defecting (a similar situation to hockey players voting for a rule mandating helmet usage, but not using them without the rule: http://www.econport.org/content/teaching/modules/NFG/Hockey.html http://www.econport.org/content/teaching/modules/NFG/Hockey....). That said, I agree with you that there should not be laws about what contracts you can make. There's been plenty of harm from that.