Well, quite a lot of traffic is already regulated by people "playing by a set of rules", and that ends up being hunky dory for the most part. I think the reason why this one is the exception is that it's quite feasible for people to "fight back" to those they perceive as abusers.

The real problem is accountability. There is none of it(as cops can't be everywhere, all the time) so people end up exercising what little power they do have in order to punish those they view as the abusers.