The majority of these stories sound like bullshit.
Truth is often stranger than fiction. If you've been around the gym scene long enough, you will have experienced situations similar to those posted above. Weirdos used to be locked up in padded cells. Now they walk the streets and are gym members.
There is this one guy at my gym. A young guy in his 20's, skinny, with long hair and a long beard. Kinda looks like Jesus. All he does is sit on a workout ball and bounce up and down for like an hour. Sometimes he'll bring a bag of cookies and juice and eat them while he does this.