I was once an afternoon bartender/waitress for a few months (between jobs) at a quaint little restaurant outside of town. Most of my customers were regulars (middle aged, executive men) who stopped for a drink on their way home from work. When I saw their cars pull up, I fixed that man's drink and sat it on a napkin at his favorite seat at the bar so it was there when he sat down. I made $10 plus tips, for working three hours each day. My regulars tipped well and I usually took home $30 to $50 a day.
One day, four (late-twenties?) men came in that I didn't know. They sat at the farthest table from the bar, and ordered beers. I brought their first round and chatted a bit and went back to my regulars. When one man finished his been in one long gulp, I went back to ask if he wanted another. He did, and I asked the others if I could get them one as well. The others said they were good and I went to fetch the second beer. When I returned, one more man wanted a second. When I returned the third man wanted a beer. They made a game of keeping me running back and forth across the empty restaurant for beers for an hour and a half. They were all very amused, my regulars were not. I remained cordial and smiling, laughing with them at my expense. One asked for my phone number and I politely declined. When they left, they left two quarters. Really?
I got the last laugh, though. My regulars made up the difference, tipping $20 each, even the one that the other regulars often teased for only leaving $2 most days. I made more that day than any other I ever worked there. The four gentlemen never came back, that I know of, and that is probably for the best.