I believe legislated morality is worse than anarchy, if the end goal is to prove our devotion and surrender our will to that of divinity (regardless of what your religious affiliation is this is a pretty common theme), then the best test of this is to eliminate the legal barriers. Someone may be more inclined to follow the law, but do immoral things that are legal (infidelity anyone?)
This program seems to offer a good solution. As long as there is an intoxicating substance available, whether it is legal or not, there will be those who abuse it. This system seems to give an out to those who would overindulge before they become a full out junkie. Are there casual drug users there? Of course, just like there are casual drinkers all over the Islamic world. The difference is these folks can get the help they need before it becomes a death spiral.