Unnecessary tangent: the main thing that makes them so good* is that they wrap them in foil before handing them to you, letting the bun heat up and steam a bit. You could microwave a cheap bun for a few seconds at home and get the same experience while saving several dollars. Or grill/toast it for one that blows ballpark dogs out of the water.
* Besides cooking them well enough, which most people don't do because the perfect hot dog takes multiple times longer than the instructions say. Simply heating them through isn't enough - blistered is better!