Went for a carvery in a pub on Sunday. Very busy, there was a long queue for food and I had to cut through the queue to get to the bar to order drinks and get a token. As I was stood at the bar waiting to be served, a man shouted to me "excuse me love, there's a queue". Looked over and man is visibly pissed off and I see that there is a small queue behind him which I had thought was part of the queue for the food. Smiled at him and said "oh sorry I thought you were part of the queue for the food" and went to join the back of the bar queue.
As I was walking past him, he tutted! AIBU to think that's so rude, it was a small oversight on my part which I apologised for and corrected! No need to tut as well.
It seems silly but it's been bothering me all day. Kicking myself for not pulling him up on it!