This sounded like the perfect idea for a social experiment.
Pretend to lose your wallet, film a person who finds it, let them go for a shopping spree and then confront them.
The problem was that people are too darn honest. It took several tries but finally one guy took the bait. He picked up a wallet and headed straight to the mall.
When it was time to come face to face with this guy, he had a surprise that turned this 180 degrees. I have to admit, it made me cry in the end.
The dude’s just awesome.