One time about 10 years ago, my front doorbell rang. I answered it and the postman was standing there. He said he had a package requiring delivery confirmation and handed me a paper to sign. I signed it and he handed me a bubble mailer and left.
I went inside and took a second look. The mailer had been slit open at one end and was empty.
Fortunately, it was a low priced chip and I never even bothered to contact seller. Who would have believed me when they had a signed delivery confirmation.