Pedestrians often cross the street when they have a 'do not walk' sign after they have checked that no cars are coming in either direction, often without coming to a full stop while checking. Would anybody argue that they are setting a bad example, and are responsible for 5 year old kids getting run over, and for motorists not respecting pedestrians in general?

Bicycles are not the same as motor vehicles or pedestrians. We have separate rules for pedestrians, and much different standards for enforcement (at least in NYC). Bicycles are not required to stay in a lane and are allowed to pass between motor vehicles in adjacent lanes, or next to the curb. Bicycles are allowed to use bike lanes and motor vehicles are not. Bicycles are required to stop at red lights just like motor vehicles but luckily here 99.9% of police officers don't worry about it.

We don't live in a perfect world although I know some people in California would like to imagine it could/should be. The discrepancy between rules and what is actually enforced give us room to handle the imperfections gracefully and give legal recourse to injured parties when somebody does something stupid. I just can't accept the very rigid thinking espoused by those on both the far left and far right. Balance and flexibility are required for any society to function efficiently and healthfully.