Explain this. If I found an object in the street, couldn't I sell it on Ebay?
If you advertised the object as being a development project from some big electronic company and sold it that way, I would expect the first people to contact you -- to be, perhaps, the police, doncha know ... :-)
Hmmm. I can see why the big electronics company would LIKE to sic the police on me, but I do not understand the law being broken. Remember that it was legitimately left behind in a public place. This is something that could result from such carelessness.
The responsibility lies with Apple. They could insist that their prototypes are only for use on their large campus.