The post office losing money is especially ludicrous because the post office is not a business— it's a public service. It should be obvious to anyone who thinks about it for two seconds that the post office is financed from the general tax base, same as libraries, highways, parks, defense, airline bailouts, and all the rest of it. All of these are run at a loss because it's worthwhile living in a society that enjoys the benefits they provide.
(And in the particular case of the USPS, it's literally enshrined in the constitution because it was seen as a pillar of democracy to be able to securely communicate with others over long distances.)