But some lucky charms do work, don』t they?

I know a person who makes a living selling lucky charms. He claims that his charms can give good luck, prosperity and he guarantees that you will be able to pick three numbers. But if what he says is true then why isn』t he himself a multi-millionaire? If his lucky charms really work, then why doesn』t he win the lottery week after week? The only luck he has is that there are people silly enough to buy his magic charms.