How does free speech include knocking on doors? I know if I was in a door-knocking sect, I'd be questioning its effectiveness. I think there are probably better ways these days, like large signs inviting people to attend worship. I asked the kids (missionaries) next door about effectiveness, or how often they got some sort of real engagement. The answer was 'it's rare'. Most preferred the in church' activities over the proseltizing. Maybe in foreign countries it works better. I wouldn't know.
With JWs, they will read the obituaries, and hit up people when they're the most vulnerable, when they're grieving. My dear MIL had that happen to her. It upset her a whole lot.