In defense of the USPS, if you think of the amount of parcels, and mail they handle, the percentage of total damage like that is VERY low. It is always unfortunate when you end up in that percentage, no matter how low it is, but, "stuff happens", and apparently this was "stuff". I will always defend the USPS, because one, it is a part of our history here in the US, and actually a huge part. And two, they are the ONLY carrier that will drive to your house, pick up a letter, and take it 2500 miles all the way across the country for lest than two quarters. Ask UPS, or even FedEx to do that, BAAHHAHHAHAH.
But, it does amaze me the damage that can happen sometimes. When I owned a graphic shop, I had purchased a used commercial plotter/cutter. A $7,000 used machine. When I got it, (this was UPS however), the box looked like it was dropped out of a 10 story building on it's end. The box was hap hazzardly taped up like a comical attempt at a box repair, and the box litterally looked like an accordian bellows. The plotter was completely destroied, and not one part of the thing was savageable, even the heavy commercial built chassis was bent beyond repair. I felt sick to my stomach, but felt secure, because I had paid for insurance for it from UPS. When I filed the claim, they and I kid you not, sent me a check for $500, and told me if I thought I could get anymore out of it, to simply sue them. They actually told me that, even though I had it insured for $5,000, they still would only pay $500, take it or sue me deal. Yuh.. I simply don't do business with UPS since then..
But back on subject, these things happen, but taken the volume in account, is very low percentage..