Raver, you're absolutely right, crew can be just as reposnsible for stealing.
However of the list I wrote the following we found with the pax or were in obvious display in their luggage.
Seatbelts - we asked to have them back, they refused, security were called and after being searched they were fined and charged with interfering with safety equipment on board. It is a criminal offence.
Lifejackets - same thing, had them searched after doing a life jacket check and they were found in their hand luggage, again they were fined and charged.
Of the uniform pieces one was a crew cardigan which they tried to wear off the aircraft walking past all of us up the aisle, it was hilarious and no they weren't drunk.
All the other items not being safety just make up part of the airline's loss. I do get upset though when it's personal items or money that has to be accounted for. Mobile phones seem to be the thing at the moment too.
And yes over the years I've seen plenty of crew bags stuffed with goodies from the a/c, as I said if the temptation's there they will do it.