I hear 521 has new ownership. If so may I offer a few suggestions.
1. "Thank you for coming in" would be a nice gesture.
2. The Sunday bartender needs a little update in her training. DO NOT ever put the nozzle of the beer tap into the beer in the glass.
3. $2 upcharge for onion rings is a bit silly. I was charged the $2 and got 5 rings. Guess what! You aren't going to make your overhead on rings. Be a little more generous.
I would be surprised if I hear back from anyone in management. Too bad cause 521 was once one of my favorite places to eat.