If you don't want people to use their intelligence, drive and desire to win - then legislate accordingly.
But expecting those that can, to not 'hide' money in off-shore funds and tax havens is foolish.
Change the rules and the players will adjust accordingly. It's the law makers that need to take notice.
"We've had leaders who had tax returns like (Winston) Churchill that would have been more difficult to defend in public than Prime Minister David Cameron's tax returns - but Churchill was the greatest leader of modern times. "So we're going to have to bear those things in mind and not expect everybody to be perfect or everybody to be normal."