He’s right. He, and anyone with him should drink for free.
If they think not, he should leave and go to the next closest bar. Then the bartender would have lots of room to sweep up and wash glasses.
Sorry, but you are wrong. There’s no written law that says he gets to drink for free just because he’s Ben Roethlisberger. As a former server myself, I can tell you that no matter who the hell you are, you offer to pay. Nine times out of ten, you’ll be comped anyway. But if you act like an ass and just walk out, the bar will be entitled to call the cops.