Atem used magic to change the card on top of his deck and everyone was ok with it.
I guess people in yugioh don't really care about cheating or not as long as the duels deliver entertainment and drama
Judai/Jaden's deck was so bad that the other duelists he faced had to have a bad enough deck for Judai to have a fighting chance (Ryo/Zane was an exception tho). Talk about scripted.