Unfortunately, I have to agree with Joe. There are far too many USPS employees that just couldn't care less. The proof is in the many, many repeated horror stories, just like this one, on here of this type of thing happening and the reaction of the USPS when it does is almost always negative.
My Postmaster is one that is awful and could care less and he told me so. When my birds were missing for five days, he said there was nothing he could do. In the end, turned out it was his fault, long story, but I asked them to check to make sure it was safe to ship when we did, and in fact, we were not supposed to ship then and they sat in a warehouse for days and then were returned to me after 5 days. Then he tried to tell me he couldn't refund my money, even though they didn't deliver the birds at all, let alone in 3 days! He said it was because I bought the postage online, I had to get my refund online. I couldn't find anyway to do that and thought I was out $70, but thankfully someone on here pointed me to the right spot that proved I had to get my refund from the P.O. I printed it off and marched it in to him. He was NOT happy.