If you believe there is such thing as a sex addiction, you can't say that all addictions are chemically induced. Unless you want to argue that pheromones are the cause, which would be silly. How do you "logically" define addiction? Based on the dictionary, it's a physiological and psychological need. How do you define need then? Who has ever died from chocolate withdrawal?
I agree avocados are probably yummy because of the fat content, but the mouth feel of animal fat? That sounds gross! I still do eat meat and cheese, avocados are just tastier. My point in bringing it up was that I don't think that chocolate lovers are any more of an addict than I am. And I especially don't think they should be compared to drug addicts or alcoholics.