Such a policy would also keep the real troublemakers away from their drug of choice. I'm talking about the angry, violent drunks that beat up their wives and are an embarrassment to society. People like that should be fitted with a safety collar that administers an electric shock when they try to enter a liquor store. Sadly, a great majority of the offenders are older than 21, meaning that no one can be arrested for selling them alcohol. People, get a grip.
Life's too short to drink bad cocktails.