No Nicotine Cigarettes

My wife was a pack a day smoker untill she got pregnant,stop smoking now, she quit and had 2 kids back to back which kept her off them for over 3 years. Today she is a drinker-smoker (never thinks about them durring the day, but enjoys several of them over a few Friday night glasses of wine. (she only drinks once a week max and often not even that much) My question is: If someone were to quit smoking for say 6 months or longer,Herbal cigarettes, what would be the harm in enjoying a no nicotine or a very low nicotine cigarette from time to time? I know the mantra of this board is "never take another puff" and I respect that, but I am curious if I am able to keep this quit going for 6 months if I will be able to go back to enjoying them in moderation the way she does. Sorry if this post is not approporate.