Back in the day, a friend of mine worked as a gas station attendant. He’d fill up someone’s car and after they left, he’d drain what was still in the hose into a gas can. The next customer would unwittingly pay to refill the hose before any fuel reached his tank. When he left, my friend would re-drain the hose. At the end of the day, he’d have enough ‘hose gas’ to fill his own car for free.
Learned that trick 25 years ago. Click off the handle, hit whatever you needed to to shut off the pump (now is setting the pump handle back in the cradle), then squeeze the handle again. Empties whatever was in the hose by gravity into your tank. Not much, but every bit counts.