Maybe the better question is not "are these people to blame for the poor image of cyclists" but "Why don't cycling advocacy groups do more to educate these people on proper cycling safety and help them find suitable yet affordable bicycles to use for transportation?"
For instance, a cycling advocacy group could team up with the local court system to provide information and even donated bikes to folks who lose their licenses. Similar things have been done to get drug addicts and alcoholics into rehab programs.
I think this is an awesome idea. It would probably also help lower the number of bikes stolen in this area, since I know first hand that bikes around here are stolen and then "sold" to the homeless, drug addicts, etc. I was lucky enough to recover mine when it happened to me. The big question I have is how to get it started? There is definately a need in the area, but I don't believe it's currently being filled. Are there successful programs like this that I could contact to help learn what the right channels are to move it forward? And then I'd have to figure out how to move it forward with local government. But I think that if bikes came with a good strong lock, lights, a helmet and some instructions about safe riding, it could be very successful.