Here's one of mine. People at grocery line checkouts who A) Wait until all of their groceries have been scanned before they begin to swipe their ATM card to pay, and then they take forever acting like it is the first time they have ever used a terminal at a grocery store. B) Same scenario except the person waits until all of their groceries have been scanned, and then and only then they slowly reach for their checkbook and begin to slowly write a personal check, while they could have had everything filled out except for the $$ amount.