[kodah]

The correct phrasing is, "Alcohol is the worst drug to be addicted to". Slightly different from OP, it just removes morality from the issue.

I definitely understand your apprehension to this idea, however, someone I know very intimately is an alcoholic. They've said this phrase to me before and it wasn't clear until they explained their position from their perspective:

There is no other drug that is as socially accepted and harmfully addictive as alcohol. Keep in mind that you can die from alcohol withdrawals and even without dying you might wish you had. The same drug that can do that is stocked on shelves, easily accessible, advertised on TV, and passed out for free at times. Additionally, addiction to alcohol is cyclical. Many people drink out of anxiety, that anxiety is cured while drunk until the person begins to sober up. Then the alcohol fuels more anxiety which continues the cycle.

This phrase isn't meant to discount the experience of other addicts but moreso to express the unique difficulty that alcoholics may experience in the world.