This is sort of a southerner thing. Up north, many gas stations actually ask you to keep your engine running while you pump. Because when it’s -20 degrees outside, turning your engine off is just asking to get stranded. And if you get stranded at a gas station overnight, (like when the lobby has closed but the pumps are still active for card transactions,) there’s a good chance you’ll be dead in the parking lot by the time the morning crew shows up to open.