I had my own failure to open the box bite me in the butt a couple years ago, and ever since, I have opened and inspected even new guns upon delivery to my FFL before I sign the 4473’s. I ordered a Marlin 60, picked it up and the box was still taped shut from factory. Sign and drive. Get home and realize the stock was broken completely in half at the wrist. Remington/Marlin sent me a replacement for free, very quickly, and my shop was offering to challenge it with the shipper.
I tend to assume any time a firearm is shipped, it WILL be dropped, kicked, and ran over by someone in the chain of custody.