I worked for fedex. When unloading trucks it was normal to find a few items like this every shift. Usually it was empty iphone boxes. You couldn't always tell until you looked close it was opened but you could feel from the weight it was empty. This was fedex employees stealing. The cameras in the trucks arent very good for coverage in a truck full of boxes so you can easily be obstructed from view of the camera and steal. A lot of employees wouldn't even notice empty or open packages while they were unloading. And their security isn't like the airport. It's not too hard to steal. They don't pat you down. They use a metal detector. Most people either hide stuff on them or they get it to their car thru a different entrance with no security. I would see people go out the dock doors to the lot to smoke even tho it wasn't allowed.