First, move to Columbus Oh, everything is better there
Second, sidewalks are for pedestrians, not for adults on bikes. It's less safe all the way around, because once you give up your spot on the road, eventually you are challenged with reclaiming it, which means potentially darting out in front of a car.
Third, cars don't look for bikers on sidewalks, so if you go over a cross street, they may make a right turn and run you over.
Fourth, initially, I was sheepish about taking up road space and 'holding back the car drivers'. All it takes from them is a little patience and a punch on the gas pedal and they are past you (except for that type of driver who is scared to pass someone on a bike, but that's another topic).
Now that being said, there are a few spots in my commute where I do hop on the sidewalk, but they are all leading up to traffic lights, no bike lane, and cars right up to the curb, such that I either have the choice of possibly sitting through two red lights to be a proper rider, or hop the sidewalk and get to the front of the queue for the green light. However, if I do encounter a pedestrian on the sidewalk, I either get back on the road, or stop and let them walk past me. It's not fair for walkers to have to dodge bikes on the sidewalk.