I think some of it is the hit-and-run aspect. I've noticed that the comments on newspaper websites and such are much more sympathetic in the H&R cases than in your typical "inattentative driver kills cyclist" story. It seems that that extra dose of irresponsibility and criminality seems to push the scenario into a different category for a lot of them. Perhaps it's that they can identify with the drivers in the "normal" cases, but not in these ones?