Long, long time ago, I was on a business trip to Cincinnati. Went to a bar in Covington, KY, with an older co-worker (Tennessee grad) and our company's field engineer on the local project.
Sitting in the audience, few tables back from the stage where a pretty good local band was performing.
Couple tables in front of us, closer to the stage, was a couple that was having a discussion and next thing I know, they stand up and this guy smacks the snot out of the girls head.
Being the refined Pittsburgh gentleman that I thought I was, I get up to defend this lass. My coworkers both reached up and pulled me back into my seat, stating it was a local matter and let the locals settle it.
While the locals settled matters, my view went to the bands drummer who was watching this unfold. The smile on the drummers face as he observed the proceedings, while keeping the beat was priceless.