I was actually behind a guy at a McD's drive through a few years ago who leaped out of his car, confronted the guy who was in the car ahead, and decked him. I guess the guy in front hadn't moved up quickly enough to suit the other one, not sure what set it off. They both got their respective orders and drove off without further incident. It was bizarre, to say the least, and the restaurant workers didn't seem surprised when I recounted it to them, since it had taken place out of their line of sight.
It was not too long ago that I was honked at at a drive thru...
What did they expect me to do?