I disagree with your assessment--you're using the term cult, but ignoring the negative connotations associated with it.
The 12 steps form a framework for posing social interraction. What makes it work for most people is that the addict can look to others who have navigated a similar path. Addicts help other addicts as part of the program. They do so, because they gain insights in so doing.
A better analogy than cult might be that it's like having a personal tutor in a subject you continue to fail. He makes you do some of the homework, but a good tutor will get to know you, what you're capable of, and help you apply what you are capable of doing to problem solving on your own. He doesn't do the homework for you, he helps you so you can pass the test on your own.
Many addicts fail AA because they don't have the social support. They need the addiction because it helps them cope. They may not even understand the "why" behind the addiction (imo, most addicts don't understand why... and often when they do, it isn't very compelling.) And they don't have the support of someone telling them that they're better than their addiction, and that if they conquer it that there's a better life awaiting them. So they give up.
AA is not just about creating an emotional high. It is about distilling in the addict ideas and actual tangible steps that they can work on. Unfortunately because addiction is often deeply ingrained in self-image/self-loathing, it sometimes comes across as more touchy-feely, but most people need some sort of training when it comes to emotional maturity. Over time, that's what comes of the program.
But don't discount support, it is an essential human motivator in most things we do. Imagine attempting to do anything momentous in your life without it... it just doesn't happen, unless you're oblivious to the way others motivate you and hopelessly narcissistic.