I obey all the laws and I get some crap for it. When I stop at a stop sign, I will sometimes nearly get rear-ended by a car, and I've had cars swerve around me, throwing up gravel while THEY run the stop sign, irritated at me for stopping.
What really amazes me about this is that the stop sign running is even being discussed. The two have nothing to do with one another. Even if you could prove that the drivers followed the cyclists and ran them off the road because he observed them running a stop sign, it's still a horrible act (and every bit as illegal). Someone doing something marginally illegal but harmless does not then justify threatening their life.
You might as well justify school shootings by saying that you had evidence that some of those kids jaywalked on the way to school.