I'm not a big beer drinker, but I tend to buy obscure dad-beers which are produced by big brewers but for whatever reason no longer get any sort of marketing push.
My selection in recent months has included Club, Old Vienna, Extra Old Stock, Labatt Blue, Molson Genuine Draft. My next visit to the beer store will probably see me buying a case of Standard Lager, or maybe Molson Dry.
I usually keep some Half Pints or random Belgian beer on hand for hipster guests who can't tolerate drinking a Labatt or Molson product