Hello Bill-

     Heck, it's still common for me to go to the garage to "work on my bike" but work on a little whiskey instead.  Those bottles usually just get put into the recycle bin because the wife knows what I am up to anyway.  I don't know why your bottles would be stacked.  I think someone was hiding a drinking habit.  Certainly there are other more pleasant places to hide bottles if they are to be reused.  Have you looked around the place for evidence of a still?  I would think whiskey bottles would get hidden away nearer the still.