A friend is a gas station repair guy. Replacing missing hoses is his most common job. It happens so much, pumps are now equipped with shutoff valves so only the gas in the hose is lost. That's why they stop working when you pull too hard on the hose, you trigger the valve to close.
He also has a side business reselling left behind gas caps. There are still plenty that aren't attached to the car itself. He just picks them off the top of the pump and sells them on ebay.