Kohn actually brings up that specific example, and suggests that bribing kids becomes a cheat that saves parents from solving the actual problem. I'm torn. On one hand, that can happen, and it can mask issues like giving them sugar right before bed. On the other hand, kids do lots of things for stupid reasons that they will cling to furiously but will let go of without pain if you distract them for long enough. This is one of many things in which he adopts a blanket don't-do-it policy when I'd prefer a discussion on when and when not to do something.