A drunk guy walks into a bar and says to the barman - "Drinks are on me , set everyone up and get one for yourself too" The bartender pours everyone a round of drinks, and also one for himself, then says to the drunk guy "that will be $42"
The drunk guy says - "I don't have any money to pay you" So barman drags the drunk outside and ruffs him up something terrible.
The next night the same drunk guy walks up to the bar and tells the barman, "Get everyone a drink on me, and get one for yourself as well."
The barman thinks it over, and concludes that this guy can't be dumb enough to come in the bar two nights back to back without any money, so he pours everyone a fresh drink, pours one for himself, and tells the guy, "that will be $61."
The drunk says 'I have any money". The barman pulls the drunk guy outside and ruffs him up again.
The next night, the very same drunk comes into the bar and tells the barman to get a round for the house. The barman says, "What, you're not going to buy me one?"
The drunk responds, "Not this time, you get mean when you drink."