Not to mention that I've seen it myself too. "Don't write it or say it to anyone but we actually kicked X from the band, he's such an a**hole!" Then meeting a really angry X the next week: "Those pigs! I'm a better songwriter and guitar player than Y and he can't stand it, therefore he and the other cowards fired me!" But officially, it was all "mutual agreement" and everybody's happy.
I've seen that, too. Up close & personal.
Thing is, though... Nine times out of ten, X has an overinflated view of his or her abilities and, thus, really is an asshole.
Just because someone says they're better than someone else doesn't make it true.