Well, sometimes they are stolen! Friends coming out of Aruba report camera and telephone batteries and an electric shaver taken in a bold face theft with security as an excuse. The screeners laughed in their faces!
So called security workers at DFW have been accused of 'shopping' in passengers property and confiscating what they want for themselves or their SUPERVISORS! Containers of confiscated items are taken to private areas where they are sorted through for anything of value. Destroyed hell!
One thing to do is report missing items to your insurance company. Perhaps large insurance companies can put pressure to improve this system.