One thing I can't stand is when people hand me $20 bills for something costing under $10. Then I have to give them all this change back.
Please be considerate and give me the exact amount or something close.
The worst is when you first get on the register and they give you a high ass bill like a $50 for a low purchase total. We only start with $75 in the register, which means I have to ask for change to fill back up the register and it's just a hassle.