I am so far beyond ticked off I need to watch my language. The USPS maintains they legally sold the package as unclaimed freight. They also agree they never delivered the package. They also denied the claim because I could not provide sufficient "proof" of value. That is the big picture. They state they have no duty or responsibility to retrieve the property regardless of how or where it was lost or stolen while in their possession, it is too big a deal for them.
Drilling down a bit, once you make a claim, they claim they own the property, whether or not the claim is paid and they legally can sell the property.
You are required to make the claim no more than 60 days from the mailing date. Why, any package which has not been claimed or delivered within 60 days for any reason they can do with as they like. Why it was not delivered or claimed is not their problem.
Now, UPS is no better, except, I understand they destroy unclaimed freight so there is no perception of profiting from the situation. And, in the case of another customer, Scott got the address wrong by one number, the last number, and so UPS delivered an ABBA set to a vacant lot and claim no responsibility for it's loss. I just wonder if UPS is in the habit of delivering things to vacant lots, you know, like, drugs and guns, to recipients who intentionally give fake addresses.