I hate to use the common refrain, but it really seems to me that a higher percentage of bicyclists drive like maniacs. What purpose, exactly, does driving without a light at night serve? Especially when combined with barreling through a red light into a multi-lane traffic circle? And, of course, sidewalks are meant to be driven on — wouldn't want to lose your bicyclist card for ever pushing your bike. Leading to the ever popular driving across a crosswalk (I'm not so sure who's at fault if I were to hit a bicyclist on a crosswalk, and I'd rather not find out).
Granted, due to the lower weight of bicycles, accidents are considerably less deadly, but there is still a considerable injury risk to me as a pedestrian, and as an automobilist, I'd rather not have an accident on my conscience, whether I'd be legally at fault or not.