I've toured for years and will admit I've been really lucky. Several years ago I started carrying an outlet tester (you know the one with two wires and a light in the center?). This thing is really compact and lightweight. I'll stop at parks that have a shelter and check the outlet. I almost always get lucky and can sponge some electricity to charge my headlight battery pack and/or phone. However, lately I have been feeling a little wierd about it.
This year I'm planning on trying a small solar pack. I have a 900 mile trip coming up and will test it then. I've read decent reviews about the solar charger shown in the above post. I'll probably still take my outlet tester...just in case.
Jerry H