I think you're reading into my comment, I was merely stating why UPS and FedEX don't deliver mail and why comparisons between them and USPS are difficult to do.

I think you're reading into my comment, I was merely stating why UPS and FedEX don't deliver mail and why comparisons between them and USPS are difficult to do. Though for completeness there have been people who've competed with USPS in the past, Lysander Spooner is a notable one.