We have both rural route delivery and PO Box delivery.
Being treasurer for a couple of organizations and having the mail stolen, we decided to go with a PO Box years ago. Then we moved to the country and lived in town so it worked well.
Now my husband retired and gets his mail delivered to the house, and I still use the PO Box. The dentist office asked me last time I was there if we got a divorce!?! Not sure what we'll do when I retire.
I did tell him it wasn't very wise to put mail in the rural box the night before and put up the flag. That's just an invitation to come see what's in the box. He'd never thought of it.