Been too long for me to recall specific stops, but then again we were usually doing that leg banzai-style.
I don't recall any difficulty with finding fuel or food, but the rigs we used carried anywhere from 34 - 100 gallons.

I think as long as they have gloves & wipes for gas stops & such, they should be OK.
I'd probably bring a mask or a cowboy/outlaw scarf, too.
Cleaning the car - handles & interior - would also be a good idea.