Wall Street Journal reports today on a little-noticed Washington court ruling that could spell the end to the three-tier alcohol sales system used in many states, including Arkanas. A court there struck down regulations that prohibited central warehousing by retailers, volume discounts and credit purchases.  If the rules change, the theory goes, it could mean lower prices., Major retailers like Costco and Wal-Mart (which want this change, of course) might eventually be able to buy direct from beverage makers, rather than wholesalers with fixed prices. It’s a ways off, but Wal-Mart’s push to expand alcohol business (remember the Sam’s liquor outlet in Fayetteville?) only prepares it for the day. Mom-and-pop grog shops best be wary.