For most of its history, Costco's identity as a wine and spirits retailer was one of the best-kept secrets in American retail. Members who wandered into the beverage alcohol section of their local warehouse discovered an extraordinary assortment of premium wines, artisan spirits, and craft beers at prices that defied comparison — bottles of Grand Cru Burgundy, aged Scotch, and premium Cognac sitting alongside Kirkland Signature spirits that routinely outperformed famous name-