But don’t forget that commercial mail is a source of revenue for the post office. They aren’t interested in giving you ways to opt-out.
My town has no home mail delivery; only POBoxes. I’ve used the info I found online to let all the direct-mail companies etc. know that I don’t want to receive mail from them. However, some companies buy out every POBox at the site; the mail comes addressed to occupant at this Zip, so I’m not in that company’s database and can’t unsubscribe. The post office simply takes the bulk mail from these folks and puts one in every box, just a like an office memo at work.
There’s no way for me to not receive that mail. Because the post office is selling us in bulk.