Alcohol is one of the worst "drugs" on a personal/societal harm scale - if we're going to tolerate this at large, we should probably consider legalizing everything else that's less harmful to at least be consistent. While we're at it, let's de-stigmatize the abuse of substances and treat it like a real mental health issue.
What is the value of "consistency" in this matter?
• making it easier for non-experts to reason about the law
• consistency is, in my experience, usually a property of fairness