Like David I get fuel at the Flying J, pay at the pump, either car diesel or at the RV pumps, and my Frequent Fueler card will turn on the pumps without me having to go in, and I still get my shower credits by using the FF card.
Swiping the FF card activates the pump and it will then ask you how you want to pay, with Option 1 being cash (or credit) to be paid inside the store after filling up, some have Option 2 for pre-paid check, and then Option 3 by Credit Card at the Pump.
I don't pay with cash much anymore, but back when I did, where they make you go in and pre-pay, back when it took less than $50 to fill up the car, I'd go in and hand them three 20's or a $100 bill, and I'd make them give me a receipt for the deposit. You go in and leave a deposit, go back out and pump, then go back in and get your change and receipt. Going into the store twice to buy something once just chaps my butt, so I made them give me a pre-pay receipt just because it annoyed them, more than anything.
But at other places (like the TA) where they want to hold on to my CDL while I go back out and fuel, I make them give me a receipt with their printed and signed name on it for my CDL (or whatever collateral they want me to give them). If they can't trust me to pay, then I'm not going to trust them to take secure care of my CDL. I do it mainly to annoy them, and it does. It's funny when someone gets upset because they think I don't trust them and/or because giving me a receipt is such a burden for them, but the fact is there have been many times when I've given one person my CDL, gone out and fueled, and when I go back in that person is off doing something else and is not at the fuel desk.
Taking a picture of them holding the CDL or card is a good idea, tho. I like that one. It quickly solves a lot of potential problems.
But mostly I pay at the pump, usually at the Flying J.
