I think not all addicted gamblers manage to get out of their own addictions. That's why treatment center/rehabilitation center or on what you call it helps the person who's addiction is severe enough that it need help from others. You have a strong self-awareness if you cure your addiction by yourself.
Yes, maybe many of them are not realize that they actually addicted to gambling. If they can realize and they want to talk with other people, I think visiting the treatment center or rehabilitation will be the best option for them to solve the problem. Hopefully, if they can get cured of the addicting, they can spread and ask other people who have the same problem to go to that treatment center. We cannot say that we are not addicting, but people out there can see clearly if we are addicted or not.