What's the rudest or funniest interactions you've heard in shops recently?

I had a hard time figuring out how to word this title. Subway is a hive for rude or funny interactions. I was in line yesterday and the girl in front ordered nachos. When being asked if she was okay with cheese or salsa etc, she kept going 'Um, yeah, oh course? It's nachos!' and then she threw a wobbler when the worker put on sweetcorn on her sandwich.

I also enjoy listening to old men trying to flirt with the women working in Starbucks or Costa etc.