Does this happen to any other women?

There have been several times when I'm out road tripping with a guy and we stop at a gas station for a quick pee break, fill up and snacks. Several times the bathroom is just a one seater for both the men's and women's restroom. Several times said restrooms are side by side and share a wall. Several times while I'm in there the guy will knock on that shared wall. What is it about a shared bathroom wall that compels a man to bang on it? I've never felt that urge. In fact, I try like hell to touch as little as I can in public restrooms.