I think that finding free camping outside when you are in some shit nothing town is probably the most important skill to have, which is easy with satellite maps. Once you get the hang of it you realize that every town has at least one site where you can definitely get away with pitching a tent for one night. I think I have camped this way about 80 times and have never even been asked what I'm doing. That said, state…
Counterpoint on RV centered "campgrounds": they have sweet amenities like a grill, a pool, laundry, and often a building with some air conditioning and some books previous guests have left behind. Not an every night kind of thing, and you're unlikely to find much in the way of grass to put a tent on, but I stayed at one with another guy who was bike touring and we get like kings for the night. When you're digging hol…
Overall I found it to be a net negative to stay at an RV park. RVs produce a lot of noise, almost on the level of night in a major city. At home in an RV, people stay up 2-3 hours later than you do on a bike tour, and they run tvs, ACs, generators, and make excess light. The last straw for me was when our "neighbor" for the night was yelling foul, abusive things at his wife. And those bathrooms... sometimes they are a real horror. Keep your boots on.
Those types of experiences are really yours for the taking for little to nothing when you tour. Toilets are so easy to come by. Showers, too, for the price of a $15 day pass at a gym, but you can also just sponge bathe in the handicap stall. I would stop in a town and get some mcdonalds, eat it at the laundromat, hit the post office, talk to bums on the street. When I wanted to swim I'd just find a place to swim. That stuff is the real gold, being resourceful and a massive cheapskate somewhere you don't know anybody.
On top of all that, you can just sneak on to the RV park in the morning if you want to.