Well I have no confidence in today's USPS, the USPS was part of the US Constitution due to Ben Franklin.
Just an anecdote our mailman and my dad always had a beer at the local bar.
Here’s a story that appeared in Reader’s Digest many years ago. It’s supposedly true.
A little girl would write her far-away grandmother once a week or so. Well, one day the grandmother took out the letters (she saved them all) and looked at the envelopes.
The little girl never once used a stamp. She just drew a face where the stamp was supposed to be, then dropped the letter in a mailbox.