You already said it works. If it works keep doing it.
Im in the commercial sealcoating business. Everything i do is essentially "door to door"
I go into businesses who werent thinking about their parking lot, find someone with papers stacked on their desk a mile high in the middle of 100 other things. And then I have to get them to stop what they are doing to listen to someone talk about something that didnt cross their mind before I walked in there.
Its not easy. You get a lot of rejection. But it works. It works better when I put my brochure on their paper filled desk than if it comes in the mail and ends up there.
Trying to figure out how to get rich and not leave my bed.