I read a long time ago, the taller the sign, the more likely it is readily accessible for tractor trailers. Like others, I just go around back and use the truck lanes.
Getting off of the interstates then raise their own challenges and makes stopping trickier. But, we've always managed it until the other day. We got down a fair amount under 1/4 of a tank - I was not happy by the time we got to the campground. I actually parked the camper in the overflow lot and got fuel before going to find a site (first come, first served).