I dunno, maybe AIBU is too nasty. Or maybe its a welcome slap to wake you up when you're being silly. Or maybe its like a nice big bunfight where people can put on the judgy pants and let rip in a witty, barbed but no hard feelings kind of way.
Whatever, it is what it is. AIBU to be annoyed/bored by people who get all defensive/ mortally offended/ weepy at being told they are being rather U?