A few months before my crisis of faith that lead to my DFing, I had a similar experience. I was riding my bike down a fairly major street & saw a wallet lying on the sidewalk. I picked it up & looked in it; sure enough, there was ID, etc, and a good bit of cash (I didn't count it - why bother, since it didn't belong to me, and I knew I could find the owner? - but there were quite a few 20's, so I know it was significant). The owner's address was only a few blocks away, so I turned around & brought it back to her, an elderly lady.
Like's been said before, SICKENING. That these people would talk about faith leading to works... And then STEAL just because they can get away with it. For me, the issue was right & wrong (plus, LOL, "Jehovah's watching")... If you can fail such a simple test, then really, where is your faith?