I had a friend in Michigan, an old high school buddy, who was put on probation for taking a leak behind a Circle K convenience mart. That was his story. The a few years later he did some time for exposing himself while driving past a school bus filled with girls. I always thought that his compulsion could have been different with an outlet. He was a product of a repressive society, if he could be in a more nudist environment he would not have the associations that gave what he did in its context. He associated the nude body with sex, excitement, arousal, naughty and special, with an emphasis on genitalia. The society gave him that.
I never got to talk to him about it all. Haven't been up there in many years. So, certainty eludes me. There is most likely more to it, but basically.... He had a rebellious nature, he didn't get much female attention in High school, dunno what he was feeling, he could have found other ways to deal with what was deep seated, but basically, in a different orientation out of common social context....
Jbee