My mailbox is full of junk mail and it’s hard to make them stop. It’s not even addressed to me, just the mailbox location. The design pattern to “unsubscribe” or block the junk sender is also useless. Surely there must be a strong political lobby in the US who don’t want to prevent junk mail. It’s so wasteful and ridiculous (literally tons of paper) and I’ve resigned to this fact of life in my country.

Marketing mail is a significant (maybe 25%) portion of the USPS revenue and very profitable. They have a strong disincentive to reduce the stream of junk mail going to your home.

What stops them from sending the spam to the same code?