True. It's a performance art piece mostly. [it doesn't stand
   alone as art - it requires participation]. Much of post 60s art
   tries to include the audience as part of the artwork so much
   that the art is impossible without them, as opposed to earlier
   art which could stand alone, be viewed at any angle and from
   many different "perspectives" (choice of paint, technique, use
   of colors, style, etc) as art.