$2 to non-ass bartender

Saturday night Bud and I went out with friends to a nearby bar. It's overpriced and the clientele is, on-average, at least twice our age. But it has lots of pool tables and live bands sometimes and a small dance floor. So we've been a few times. Bud went up to the bar and ordered two pitchers - for the 6 of us, not one for each, as I would have it. The bartender told him they had no domestic beer, which they did last time (what is it about bartenders and the odd power they yield?), to which Bud muttered, "gimme a break," to which the bartender yelled back, "YOU give ME a BREAK! I'm the only one back here!" I thought for a minute he was going to either dissolve into tears or jump across the bar and grab Bud by the throat. It was so unsettling we both just kept looking at each other like, what? Did that really just happen? After a while another bartender showed up and so I played the little game of "avoid seriously unhinged bartender and order from the other" but somehow, I still live with my mother kept asking me what I wanted. At the end of the night Bud asked me whether he should tip the bartender at all. I said, yeah go ahead and give something small so as not to be a total jerk, but maybe you should specify that you really only want it to go to the other, more seemingly normal employee. The next morning I pulled the receipt out of Bud's wallet just to see what he'd written. Also, not to worry, I was able to snatch plenty of marischinos and olives on the way out as retribution.