When I was considerably younger I did a lot of road biking. I tried to be a good citizen and stay out of the way of traffic. I was hit once, by a lady who blew through a crosswalk as I was *walking* my bike across the street. She did not stop. I was not hurt, but my bike was a bit bent up.
With all that said, there ARE cyclists who are stupid, oblivious, and hostile. Case in point:
I used to live a block from a winding, hilly, narrow two-lane asphalt road. It was the main thoroughfare from the south side of the community to the north. No shoulders - just a ditch on one side and a narrow sidewalk on the other. The local bike club (out of Atlanta Cycling a couple miles north of the road in question) decided it was a GREAT place for a group ride. Very dumb.
I came over a hill on a curve, doing under the speed limit (35) and there was a whole crowd of cyclists coming up the other side of the hill. They were not obeying the law here which says no more than two abreast - there were 3 or 4 leading the pack, and the outside one was IN MY LANE. I slammed the brakes and hit the ditch to avoid hitting him, and he and the rest of the mob shot me the bird and bobbed off, without stopping to see if I was all right (I was, and my car was fine too.)
I went straight down to Atlanta Cycling and told them that I was filing a complaint with the local P.D. Didn't see any more rides on that road. Good: I don't want some idiot's death on my conscience.
When I used to live in NYC, a huge peloton of mostly semi-professional biker used to ride in Central Park every summer afternoon when the park was closed to traffic (7:00 pm). I have seen them scare the hell out of people just politely jogging along on the side of the road. It was frightening.
I tried to tag along once at the very end. That lasted for about an eighth of a mile (at best). And I was in great shape. Those guys were killers on wheels. If they were riding on highways, I doubt they would have been thoughtful.