The fallacy that anyone who has incurred a sunk cost and refuses to stop an activity. IE, applying the sunk cost fallacy when it should not be used.
Joe: Man, Jill has already blown like 1000 bucks on video games. She shouldn't buy any more.
John: Ya, but the next game is only a dollar and it is worth 5 bucks to her. Sunk cost fallacy fallacy, man.