I'm so glad when things are found! DD8 lost her pin bag last Year. She was devastated! We kept checking lost and found, but they didn't have it... Until the next morning! We stopped by lost and found right before leaving on departure day and they had it! It had made a pretty bad last day in the park for both me and her (I've passed on the worrywart gene to her). Now, I'm super-vigilant about keeping tabs on the girls' stuff and pretty much never saying 'no' putting their stuff in my backpack.
I did learn a lesson about turning things in, however. I turn everything in, and I generally go to the trouble of walking it to lost and found myself - if you turn it in elsewhere, it may not make it to lost and found until tomorrow!