Boulder, at that time, was a “dry town”  – i.e. no alcohol could be sold – even though you could buy it outside the city limits.  Thus, the only “non-alcohol” you could buy was 3.2 beer (3.2% by weight or 4.0% by volume).  Since it was “non-alcoholic” you could drink it when you were 18.  The other beer tavern that I remember on the hill was Tulagi’s just up the street (now closed).  Named for the island in the Pacific where a major WWII battle was fought depicted by a giant painting on the wall – and I think the owner’s son participated in the landing (and was killed), and the other was “TTs” or Timber Tavern on Arapahoe St. in downtown Boulder.