Quality of life
This is about kids AND quality of life. Do we want Menlo Park kids to get to experience the independence and freedom that we felt as kids when we biked to schools near our homes? Do we want our kids to get their blood flowing and their minds cleared on their way to and from school? And what about the rest of us? Do we want to be forced in our cars in bumper to bumper traffic as we travel less than 2 miles around town? Do we want to be stuck in a vicious cycle of dangerous streets - more driving - more traffic - more dangerous streets?
And as for drivers and those who can't bike...removing bikes from "sharing" the road will make drivers feel safer. When we drive (and we drive a lot), we feel very nervous interacting with bikes. And, if more people bike, there will be fewer cars, and the roads will be safer for those who need to drive.