I work part time at a convenience store in Wisconsin (it keeps me from driving my wife nuts.) OUr diesel islands take almost any credit card without having to come inside. If you are using ComData, you have to come in because we are required to check the drivers id for that one. We also have diesel at our car pumps and most of the class C's fill there.
I wish that the class A diesels would use the truck pumps because the regular pump area is not large enough to maneuver the larger rigs. I have had to go out into the lot and stop traffic so that they could get out. If this happens, don't complain to the employee who is out there trying to help you.
If a gas class A has a toad, when I see them start entering the lot, I hope that they won't try getting to the pumps. They WILL NOT get out without causing major traffic problems.