A drunk is sitting at the bar. There is a very buxom blonde a few seats down from him.

A fellow at the other end of the bar calls for a beer.
The bartender fills the mug and slides it down the bar.
The glass hits the blonde's breasts and spills all over them. The bartender goes over, retrieves the mug and licks the beer off her breasts.

This happens a couple more times.

The next time, the drunk jumps up and starts to lick her breasts. She decks him!

He's lying on the floor moaning and groaning.

"How come you let the bartender do it?" he asks the blonde?

She answers: "Because he has got a Licker License.