Our routine:
If coming from the campground, we hitch the towd after gassing the MH. I gas the MH. DW gets breakfast or does shopping and we meet in a large parking lot.
If on the road and they're several off ramps to a town, we take one of the first off ramps. Cruise through town until we find a suitable gas station, hop back on the hughway.
At a 1/4 tank, I start looking. Also a GPS will lead you to a cluster of stations.
The bad scene is when you're not paying attention and the low gas light comes on and you just passed a sign that says, "next gas 30 miles"! But then you do have a towd!
Norm