Ivey did absolutely nothing wrong. If he asked a dealer in blackjack to show their hole card before he decided to stand or hit, and the dealer did, would Ivey be cheating? He asked the Casino to do some things. They did. He didn't mark the cards. He exploited the edge they gave him.
If you wanted to play with a book, and in order to entice your business, they offered you a free point on every game, and you accepted their offer, are you cheating when you beat them badly because of what they offered you?