Yes today any station I go to requires pre-pay but years ago I worked at one that didn't, and we had this gal that drove off practically every other day. She got away with it several times because she lived in a condo complex behind the station so we were always watching for her to pull out of the lot onto the main road while she took a little path through the back of the lot.
Eventually I saw her do that and the police came, found her vehicle pretty quickly, asked me to come identify her and presented her mother, the owner of the vehicle and I said no that's not her, then they figured out who did it.
The kicker was this girl.... her sister worked at that gas station too. Heh if it'd been my sibling I would have told them to at least steal gas somewhere else if you're going to do it at all. The girl's sister HAD to have seen her come in, recognized her and their mother's car, and get gas so many times without paying.
Anyway about parking at the pump, depends on how the station is set up. The one I go to most frequently has most people parking at the pump. There are a couple spots in front of the store, parallel to it, and a row of spots along the side, but half the time those are just as crowded as the pumps because many people go there for non-fueling reasons. You can't even pull from the pumps into half those spots without waiting for them to open up and making an extra half lap around the lot which may be a path that's blocked.
As a result, practically everyone parks at the pumps to go inside.
My biggest gripe is when the manager gets stingy with # of employees on duty, especially with certain cashiers that are dog-slow so what should have been the cashier keeping up with the flow of people coming to the register, turns into a several minute wait. It's also annoying when they try to push-sell impulse items by piling so many things at the register counter that you can barely even set anything on the counter or have your stuff bagged.