Let's forget for the moment that this has nothing to do with this forum, and focus on the fact that he has the opportunity to meet MANY women on any given day at any given time in any given place.
If he's going to cheat, he's going to cheat, whether it's with a waitress or random woman he meets while he's getting fuel.
Sounds like the issue is your own insecurity and jealousy.
Grow up.