Depending on the situation - I have nothing against the sidewalk. I will gladly use it when situations dictate. I was riding on the sidewalk yesterday to just get down one really annoying stretch on the way home and there was a pedestrian there that I didn't want to sneak up on (I haven't put a bell on the new to me bike I have been riding this week) so I switched to the road until I passed. Generally I am far more cautious on the sidewalk and go a lot slower. I go even slower when passing (MUP or sidewalk). It is great to have the option to use whatever suits us (and the option to annoy drivers?). Any driver that is perturbed would be upset by anything though.