I don't have kids, but I can totally understand how that would increase one's tolerance for chaos.

I think I "don't care" because I'm very analytical. Already at a very young age did I realize that this world doesn't make much sense in that it's not very logical, consistent or fair. It's more like a game to play.

So you develop a kind of "humans going to human" attitude where you detach from drama. Or at least pick your battles.