I don’t know if this fits the bill but, for several years, I heard the story of a man who had been released from an asylum and spent all his time on the sidewalk of a large road pretending to be a tree, raising his hands and fingers as if they were branches and bushes and would wave them in case of wind (also imitating their noise). He was nicknamed after a specific type of tree I don’t remember now

I’ve never met the guy, but it stuck with me since I heard the same story from various people who didn’t know each other

Edit: grammar