As someone who's in recovery, this is a very interesting question! I initially started eating paleo in order to drop the weight that I gained once I stopped drinking and using drugs. As far as whether paleo people are addicts, I can't say; however, in my experience there are some interesting parallels between the relationships that alcoholics have with booze and the relationship some people have with the SAD. For example, a couple of the reasons I drank was to fit in, to feel comfortable in social situations, to silence uncomfortable emotions, and to sate what I later came to understand as a spiritual hunger. When I went paleo and became more mindful of eating with intention, I realized that I also ate a lot of the crap I was weak for (pizza, ice cream, and pastries in particular) for the same reasons: as comfort, a pass into social situations (birthday cake, anyone?) and to emotionally shut down.
I think a big difference between paleo and recovery, though, is the concept of unmanageability and powerlessness. Step one of Alcoholics Anonymous (and by extension most every 12-step group) involve admitting that you are powerless over alcohol, and that your life has become unmanageable. From my own experience eating paleo and knowing folks who also eat paleo, I don't find that most people's stories involve this particular sense of powerlessness — instead, people "woke up" to the logic and deliciousness of eating whole, natural foods and started changing their lives.
Now that you have me thinking about this, though, I can see some other comparisons. The second and third steps — coming to believe that a power greater than yourself can restore you to sanity, and making a decision to turn your life & will over to this power — reminds me a bit of the way that some folks put the lifestyle itself or figures/organizations aligned with it (Crossfit, Wolf, Sisson) up on a pedestal as the pinnacle of correct living/eating/exercising, and then devote themselves 100% to the process. I sincerely doubt that anyone is praying for Cordain to grant them serenity, though ;)
Any other folks in the program have thoughts on this?