The other night I went out with a friend. We sat at the bar of a lovely little place. The bartender was very helpful with their extensive beer list, allowed us to try a few things, and was generally great. What wasn't so great were some of the other patrons. Here are a few etiquette suggestions:
1. If the bartender is pouring a draft beer or making a drink, wait until he's done before walking up and asking to see a menu.
2. If the bartender is talking to another customer, don't interrupt him in mid-sentence to ask for a refill.
3. It's creepy to stand right behind someone's bar stool, as in touching the back of the stool, especially if the bar is not so crowded that you are doing this by choice. Leave a bit of personal space.
4. That Sheldon Cooper stare you have going on to try to get people to vacate their seats doesn't work. It also makes you look a bit deranged. The guy in #3 might think it was kind of cute.