Addiction is a heavy thing, though. There is a reason why even mostly secular self-help groups like AA (sounds funny on here even when I spell it out, heh) rely on some kind of deity in their programs to help the addict overcome his habitual void.
First of all, one needs tremendous willpower to go through live sober forevermore, once while he still is addicted, to take "the first step" and then for the rest of his life. Some programs are better than others in this regard, but I still think it's a good thing that there is an alternative way for people who simply cannot commit to what is required to kick the habit for good.