The trick to getting these bastards is filming them with spy cams, and then posting their idiocy on youtube and like sites. You can go down to the local Walmart and get ink pen spy cams, they sit in your shirt pocket and catch all the retardation of these morons on film.
Spy cams come in different objects. But I recommend the ink pen cams. I'm posting this note because there have been a lot of issues with them taking people's cameras and video devices.