I think everyone involved behaved poorly. Did Pierre know this guy before he went up to his table and started insulting his friends and drinking his liquor? Even if he did, it was in poor taste. But then this guy shouldn't have thrown a punch. It's much more effective to cut somebody down using your words than your fists. He should have treated Pierre the way you do with a spoiled child, which is you clearly show that their antics will not get them what they want.