Better check with Bezos, the most significant thing the USPS does now is delivering Amazon. The last two Christmas seasons Bezos had our mail carriers working seven days a week. Of course if Amazon paid the rates you or I do, the PO would be in better shape.
By the same token, I believe that we farm out packages to Fed ex and UPS....and they’re HUGE contracts.
Another thing the USPS does is deliver packages coming from overseas (mainly CHINA) for free. This is why CHINA sellers on eBay can sell items for one dollar with free shipping to the US.
Supposedly this problem is fixed, but the fix won’t take effect until later this year.
https://www.supplychaindive.com/news/upu-postal-rate-change/564615/
We shall see.
The PO would be in GREAT shape..
I’ve checked amazon packages against the rates I pay as a top rated ebay seller. many times, after weighing and measuring the package my cost is MORE than what I paid for what is in the package.
now, amazon could be shipping/selling at a loss.. but I doubt it.