I know someone who fiddles with everything. He is a little of a weirdo, similar to me, although he fiddles a lot more. He picks at things so bad at times that he breaks them. I think he has ADD but otherwise he is quite high functioning. And does he know he does this? Nope. I think he needs to to release his inner energy. For him it is more than than just a habit. I once gave him a stress ball and he had never seen them and while he was wildly squeezing it he asked me what it is for. I told him he was doing it right. He said HUH? I said what you're doing is what it is for. He looked very puzzled for seconds while he processed everything. Then he realized he was squeezing the ball. That is how bad he was unaware of his fiddling. LOL.