He doesn't have to be an Einstein to know that this guy is Jewish.
So, he shouts over to the bartender so loudly that everyone can hear, "Drinks for everyone in here, bartender, but not for the Jew over there."
Soon after the drinks have been handed out, the Jew gives him a big smile, waves at him, then says, "Thank you !" in an equally loud voice.
This infuriates the Arab.
He once again loudly orders drinks for everyone except the Jew.
As before, this does not seem to bother the Jewish guy.
He continues to smile, and again yells, "Thank you!"
He does this once again for the third time, but not for the Jew again.
The Arab gets real cranky so he asks the bartender, "What the hell is the matter with that Jew? I have ordered three rounds of drinks for everyone in the bar, all 200 of them but him and all the silly bugger does is smile and thank me. Is he nuts?"
"Nope," replies the bartender. "He owns the place."