It becomes a problem when it's used for profiling, such as "Don't hire that person, there's a 65% chance they'll be an alcoholic" or "send a drone to kill that person, there's an 80% chance they're a terrorist"
I agree that it's a problem, but your distinction still seems generally pointless. If you have a company policy to not hire alcoholics and you reject 1,000 people based upon this metric then 65% would have been an alcoholic.