So, I was watching my wedding video and I realized I made an etiquette faux pas. Apparently there was a tip jar on the bar (it was a hosted bar, not a cash bar). I didn't realize it at the wedding since I never went to the bar myself. We were told that the tip was included in our payment, so I never gave a tip jar a thought. Oh well, I guess you can't catch everything.
What etiquette mistakes have you made?