There is no bottom that activates LC! Its a sequence of buttons you press in order to activate it. Secondly, engaging LC does not void your warranty. The only way you void your warranty is, if Nissan feels like you abuse the car in some way. With this I agree, especially if a vehicle is capable of 98/2 awd! Like I said before, Nissan can not support our racing habits.
Furthermore, your analogy is completely wrong.
That's why I buy American b/c they do support our habits.