@Intrepid,
A long time ago, someone found my paycheck at a curb in Westwood Village, and turned it in to the university, where I was employed. True, it would have been hard to cash, but they bothered to get it back to me. Another time, years later, someone found my wallet and called me, all the money there. Another time, someone must have found my wallet at a gas station, and didn't call me, and I needed items in that wallet - plus the whole cancelling of credit cards business. So, I would think I would turn money in. But I might have more trouble about that with a twenty dollar bill floating by in a park than I would with 10,000. in a bathroom.