As a cashier I hate people who throw crumpled up money on the counter for me to flatten out and count, people who spend the whole time I'm helping them talking to someone else they know... Especially when there is a line behind them. They don't notice that I'm waiting patiently for them to pay... People who are on the phone the whole time I'm helping them, people who throw a bunch of loose change on the counter for me to count... Seriously, stack it in $1 increments or roll it... The people who do this KNOW that we will accept rolls of coins. People who stand in line knowing full well they are expected to pay and still don't at least have their wallets out by the time they get to me. People who spend 20 minutes trying to see if they have exact change, but I really only hate it if they're making other customers wait... If no one else is in line it's a nice break from whatever else I was doing. People who make snarky comments about having to wait because I'm busy helping a customer who was in line before them... Yes, as a cashier i know things are expected of me and I need to suck up to the customers but I do wish more people remembered that being polite goes both ways, and not just towards me but towards everyone behind them as well.