What friends and acquaintances have experienced is people stealing bikes from storefronts, etc., riding them a few blocks, then crashing them into a tree or throwing them down a hillside. This type of theft is certainly not ALWAYS committed by someone with disdain for cyclists, but a person has to have some sort of anger in them to do something so messed up.

I work with a lot of tough dudes who ride around in huge pickup trucks looking for people to screw around with, just for laughs. These guys are always talking about throwing things at "those f-ing $%&s in tights" or "accidentally" backing into somebody's expensive ride in a parking lot. So yeah, even if what I'm describing is not theft for theft's sake, it's still the act of bikes being ridden away from their rightful owners.