I only use flyers.
I wouldn't knock on people's doors. I hate cold callers.
Do onto others and all that.
I agree with your last sentence. However:
I knocked on thousands of doors when canvassing, and could count on one hand the number of aggressive responses I got from householders.
The key is to be polite and relaxed but to be brief. Above all, listen to and respect the householder and if they say they aren't interested or tell you to go away, remain polite, smile, thank them for their time and leave.
If I needed or wanted to expand my business, I would choose to canvass over leaflets or flyers all day long.
Going back to your last sentence, I get people canvassing for all sorts of things. I almost never subscribe to whatever they are offering, but am always polite and even have a conversation with them, ending with a 'wishing you all the best'.
Yes I agree with treating others the way I would like to be treated.
John