go to
register. done.
Do what I do. Put return to sender. If it has a return envelope with postage paid then have some fun and send your trash” the garbage you get in the mail” to them. (See how they like it) Problem solved.
The only thing I can think of is mark the envelope “refused-return to sender”. I live in an apartment complex, my mailbox is outside, there is a dumpster right across the street and that’s where I put mine.
You could bring the mail home, mark it refused and put it back in the letter box when you get your mail the next time.