Memories, indeed. I worked at a gas station in the early 70’s; the days of odd-even license plates and checking to make sure that people had less than 1/2 tank or they couldn’t buy any more.
Anyway, I owned a Vespa at the time, and kept a gas can by the pumps. Every time I pumped gas for someone, I’d drain the extra into my can after they left. I NEVER paid for gas!!