You're right. Those riders do a lot of harm to our hobby. Every cop in Miami now has the idea that motorized bicycles are ridden by people like them and they're out gunning for them.
Ride responsibly, ride safe and obey the traffic laws. Use common sense and you'll be good. Thanks for bringing this subject up again. There have been several previous threads on the Miami bunch and videos of their unacceptable riding style. One even showed them running and hiding from the police. That one made a lot of friends here.
We all have to worry about our freedom to ride our bikes because of riders like we see in that video, I live in Georgia and have never had one problem from police. That might change in the future because we are not the only people that watch on-line video's.