In Neo's defense - or in my own - I am not suggesting that because the police won't do anything means it's futile to report it. I am not suggesting that at all. A crime should be reported, and you did the right thing.Conclusion and advice: Throw the watch in the trash can on your way out, and forget about the whole thing. We aren't going to waste our time on paperwork just in case the other guy makes a complaint. If he doesn't know who you are, that's his problem not ours...
What I am suggesting in LisaB's case is that there is no crime to report. The police can't do anything.