I can't help but worry that when I'm forced to cross a bridge on a sidewalk I'm going to ring my bell to pass and someone's going to be so startled that they're going to leap over the railing. The poor peds sometimes have nowhere else to go on those tiny sidewalks. I think strange things when I ride.
In the winter, passing peds is a whole new ballgame. The bell becomes useless when the peds bundle up their heads and ears with parka hoods and toques (winter coats and hats for you non-Canadians). I try to just slow right down to a walking pace and pass ever so gently.
I can empathise with those peds who go for walks and find themselves a little disconnected from their surroundings as long as they don't violently snap back to reality and kill one of us passing cyclists.