In a game of monopoly you need money to play, but no matter how much money you get. At the end of the Game it all goes back into the box, but ethics last beyond the game. Next week you may forget who won the game, but you remember that you had a good time. You didn't cheat, and you used good sportsmanship.
The same applies with life. Money is important, but ethics can last when money can't.
Also, you wouldn't do something unethical or illegal to get money.