We get reports such as these and people make assumptions that this represents most, if not all cyclists. It even ignites hatred of motorists.
The range of people who bike is great. Some ride who are follow nearly all traffic rules, just like motorists. Some follow fewer rules. My estimation is that college students and the homeless are the worst offenders. 
The homeless have a higher percentage of people who have serious mental health issues and/or drug addiction. Many have had their driver's license revoked.
For some people, anyone on a bike who is not following the law represents all people on bikes. They do not discriminate between different "classes" of cyclists.
When I see a intoxicated person on a bike who is not following the law I realize how fortunate I am that they are not driving a car. 
Unless one gets satisfaction from just hating all cyclists, I suggest being more discriminating in how one views people on bikes.