Do you ever wonder to yourself, "What can I do to be a complete prick at a kiosk-run gas station?" Allow me to enlighten you, as there are a few ways people found to piss me off when I work gas.
#1: Never use your credit/debit card at the pump. Always opt to "Pay Inside" and slap your card down at the attendant's station, wasting everyone's time and adding unnecessary effort to complete the transaction.
#2: Never follow the on-screen instructions on the pump. Assume that you know what you're doing, hit a couple random buttons, and bitch to the attendant when it doesn't do anything.
#3: Never pay attention to the signs posted on the pumps. The reading material on the pumps are never important. Messages like "In cooperation with your bank, the pump stops automatically at $100 for a credit card transaction" are only for antisocial geeks, and should always be ignored.
#4: Try to pay with a check, even though practically no gas station in the world that operates out of a small kiosk accepts checks.
#5: Start pumping, and pay while you have the pump handle set to automatically keep pumping for you. Bitch at the attendant when the pump exceeds the amount you paid, even though the attendant has no control over your pump when you start it up before paying.
I'm sure, with enough time, I could come up with a good many more, but I think that's enough to get my point across. A firearm should be a mandatory piece of "customer service" equipment.