Happened to me last week too: I received an empty box that was supposed to have $70 worth of lipstick in it. I think it's safe to assume the PO did not accept the box for shipment with the neat cut along one side, but they, at some point noticed--because they stamped it "damaged" before delivering it, empty, to me! I doesn't take Sherlock Holmes to figure out the pilfering happened while it was in the possession of the USPS!! Of course the person I bought from on eBay did not offer insurance. Grrr.
Won't do that again....