The coworker who gave you a ride after the late shift never asked for gas money. Some people are just good.

Some people help without creating an obligation. A ride home after a late shift costs fuel and twenty minutes, and choosing not to mention it means you are not left carrying a small debt, which is the whole difference between being helped and being managed. Not everybody does it that way. Discovering that some people are simply good is one of the better things a job teaches.

Accept it gracefully when it happens, then pass it along in some other direction. Give somebody else a ride, cover a shift, wait with a coworker until theirs arrives. Do not make a thing of it.