I avoid the USPS as much as possible. I have found the service to be so sub par as to be insulting. I no longer take mail at my residence because the carrier was lifting items from my mailbox.
My neighbors and I have our mailboxes on a plank between two posts.
I have a notion to put a trash can under the boxes with a sign "Junk mail" and a sign on the mailbox that states "1st Class Mail only."