USPS has monopoly access to every mailbox in the US. Those boxes are installed at *customer expense* -- probably $20 billion worth of property in aggregate, gratis to the USPS. (Imagine if Amazon could force its customers to spend $20 billion for Amazon-only package receptacles!). If you don't believe me about the monopoly, look up the relevant statutes. Fedex, UPS, et al can't touch your mailbox.it's not a monopoly and in fact companies like Fedex and UPS can pick off