USPS as a public entity of the US government is required to deliver mail to all addresses. I don't know all the specific details and I'm sure there's some exceptions for getting service to a new location but existing locations cannot be removed.

There is daily USPS service to a postbox at the bottom of the Grand Canyon that is only accessible by mule paths. I guarantee this service would either be cancelled or go up in cost to thousands of dollars per letter if USPS was privatized. The sheer size and remoteness of parts of the USA is why it's a public good.

https://facts.usps.com/8-mile-mule-train-delivery/

Public goods can be contracted out to private entities. And this can be done independently in each region, without having a single central contractor.

EU countries privatized their postal services decades ago, because governments are not allowed to compete with private entities in the market (unless explicitly allowed by EU-wide laws). And because the idea felt good, the same privatization extended to territories outside the EU, such as Greenland.

> There is daily USPS service to a postbox at the bottom of the Grand Canyon that is only accessible by mule paths. I guarantee this service would either be cancelled or go up in cost to thousands of dollars per letter if USPS was privatized.

You say that like it's a bad thing.

Why does a hill billy who insists on living at the bottom of the Grand Canyon deserve a subsidy? That public money would be better spend helping poor people.