biggest customer pet peeves?

i will preface this by saying for the most part customers have been nice to me! however there have been a few who have been rude to me.

mine:

1. when i’m trying to explain the credit card and they rudely cut me off in the middle of me sharing the benefits to say they don’t care.

2. when customers just walk up to my register without me paging them over.

3. when i’m in the middle of a transaction and another customer just comes up to me to be like “you double scanned this item”, or better yet they bring an item that wasn’t even in a transaction i did for them to say it was double scanned or the security tag wasn’t removed or something.

what are your biggest customer pet peeves?