My group is a bunch of lunatic boozehounds, but we've never drank while gaming. Part of it is that we used to play in my brother's grandma's basement, and she was very strict about such things. (She sprinkled me with holy water once.)
Also, it's like salmon and peanut butter. They taste great and they're both wholesome, but they wouldn't go well together. Our beverages of choice during gaming sessions are high in sugar and caffeine, and our foods are either loaded with sugar, salt, or both.