The draw of theatre in the age of movies is that each experience is unique. 

While the script's words and stage directions remain the same night after night, the unique alchemy of the actors and audience gathered in that particular configuration at that particular moment in time, does not. When we linger in our seats after the final encore, delaying our exit into the glaring reality of the world, it is because something in us senses that this particular magic will never happen again. If we were to return to see the play again the next night it would not be the same, and neither would we. Every time a curtain falls on stage, the particular piece of art that was that play, that night, with that audience as it is that night, shatters.