It's rare to treat patients that has gambling addiction issue. Usually, those who are addicted in gambling in which they have nothing left to gamble due to their lack of control became miserable already and they have no money to pay for the treatment then. Also, the problem in ascertaining that is people who have that issue doesn't act suspicously. Usually the keep secret for themselves which makes person who are valuable or close to them difficult to know their siutation. I think with just keeping do other things can help more for them rather than putting them in facilities. It's a difficult task but still doable at the end.
gambling addiction is not a severe mental illness that must be entered into a psychiatric facility, the best way to cure gambling addicts is to do hypnotherapy. I have personally visited hypnotherapy to reduce my addiction to smoking, and there I saw many patients who have other illnesses (phobias, game addiction, hypersexual, and others) that are being treated or are almost cured.