> Funny though, it may not be the pumps. That just might be an expression of their strict cleanliness. It maybe some other aspect that actually brings in customers. Or possibly the sum totality of 'clean' and not any one thing.

In the early days, Ray Kroc focused on McDonald's always having spotless bathrooms. Moms knew this and would stop at McD's on road trips because the bathrooms were reliably clean. Nobody else was doing that at the time.

Kroc and Fred Turner would also walk around the entire block at a McDonalds location, picking up trash.

It's probably location. The busier gas stations are on well-traveled roads or close to highway exits and on ramps; the ones that aren't do less business. Location gets ignored a lot, but it matters so much.