The USPS has 2 legal monopolies, according to US code title 39:
Carrying letters, with an exception for “very urgent material” - which is why FedEx, UPS, DHL, etc are able to carry some letters, but can’t do regular ground letter delivery.
Use of mailboxes. It is a felony (IIRC) for non postal employees to put things inside mailboxes.
The USPS has 2 legal monopolies, according to US code title 39:
Carrying letters, with an exception for “very urgent material” - which is why FedEx, UPS, DHL, etc are able to carry some letters, but can’t do regular ground letter delivery.
Use of mailboxes. It is a felony (IIRC) for non postal employees to put things inside mailboxes.