explicit govt monopoly rent-seeking (law abuse)

[Anonymous via the Cypherpunks Tonga Remailer]

The problem dates from the early 1930s, when utility companies delivered
their bills by mailbox through their own employees out reading meters. The
Postal Service saw a huge drop in revenue and decided to act. Enforcement
became even more important in 1970, Dalton wrote, when Congress
mandated that the Postal Service be self-sustaining.

>From http://latimes.com/editions/orange/la-000000534jan03.story?coll=la%2Deditions%2Dorange

Postal Service Delivers Stern Warning on Mailbox Misuse
Enforcement: Agency tells Orange mobile home park residents to stop
using receptacles to send notices, rent bills, newsletters sans postage.

.....
Q: When government acts like this how are they different from a gang?
A: Both rule by violence and terror, but a gang claims no moral authority.