You do not need a permit to be on the sidewalk. That’s public property. Take it from a guy who’s handed out free literature on the sidewalks and has had to talk to cops about it.
In some states, like Missouri, you have to leave the sidewalks clear. Tree lawns, OTOH are fair game.
If I ever do the protest thing, my sign is going to say "Desdemona's wish list: hot tub, Bombay and olives."