Our little town only has a Postal Station - no house delivery. I have a Post Office Box Number, which generates a nasty note (if they put it in my box) if anyone forgets to put on the sacred number.
When I moved to Magrath, we found it easier to just piggyback on my family post box for which we just all had a key. Meanwhile, 15 years later, the Lions Club needed a box so that they could receive mail at a common location. Mr Canada Post said no. I said why not? They said because the club has no street address. So I said, what about mine (unused for the past 15 years). They reluctantly said maybe .. reluctantly .. ok and gave me my requested new box number.