Boulder is a biking town. There are many businesses associated with bikes and the biker community takes great care to protect their presence by participating in all relevant city and county organizations and regularly attend Council meetings. In fact, they are a perfect example of how any group should defend and lobby for its interests in Boulder.
On the trail the vast majority of bikers are cautious, friendly and responsible, so I am happy to discount the odd irresponsible or unpleasant biker I come across.
The problem many people have with bikers, not just V&S but also casual walkers, is that there is just so many of them and in the mud season, they destroy the trails which are then closed to everyone till they recover. Marshall Mesa OS has become an informal bike park. I have spoken to many people who no longer go there because of the number of bikes.
My personal position is that I am fine with stepping off the trail for a biker to pass safely, on the assumption that they will exercise similar courtesy when they pass my dog