I much prefer the system at many airports in Europe where everything gets turned in to a third-party vendor at the airport. The vendor catalogs everything in a database and retains it for a period of time before disposing of it at auction. You can check with serial numbers, descriptions, flight numbers, seat location, and the like.

You pay a fee and the vendor will ship (for a fee). But, in return, you get real service. I'm fine with it because I don't expect DL to eat the cost of my own negligence.