Some years back, I saw someone drop a $20, and I stood on it until the guy was out of sight. I stuffed it in my pocket, and somehow I ended up dropping it as well.
God taught me a little lesson that day, as He is wont to do.
Since then several similar situations have arisen, and it never even occurred to me not to do the right thing.
Temptation comes in all denominations!
And God does have His ways of teaching us stuff.