I used to be a trucker and I'd see RV pulling in thru the pumps the wrong way many times to fill the DEF tank. Not really a big deal if the truckstop isn't busy. Pilots are usually a very small truck stop and going thru the wrong way can be next to impossible without getting stuck. Flying J's, loves, TA's and Petros are generally a lot bigger in size, so pulling in the wrong way isnt a big deal since theres no chance of getting stuck unless its busy. Just be careful if you decide to fill a container and walk it around to the other side. That stuff is super corrosive, don't spill it on anything important.