Anyone who steals the $50 bill and turns in the purse is just stupid.I remember reader's digest did a test on honesty of certain clerks and they turned in a purse with a $50 bill in it and of the 10 times they did seven times the money was still there three times it wasn't.
So it could be that maybe someone did turn it in but somebody had light fingers at the police station and I know some people think "How dare you think this!" it's like well, we've seen worse out of certain police.
Oh, check the pawn shops nearby if possible, could have been hocked.