When camping in Europe you will find many "pay" campsites, use them. A friend of mine was telling me of a friend of his who refused, ( "too cheap"), to use the sites and camped "rogue" by himself and was forever having things stolen while he was sleeping, so- he didn't save any money and ended up paying more.
Ask the locals, bikeshops etc. where to camp, often they'll know a super spot or invite you home.
Ride Far
Pat