What would you do in this scenario?

This should be simple: Did you actually see the movie? Under what circumstance did the user tear your ticket stub? This should be your guideline: If you actually got to see the movie, regardless of what day your ticket was for, then you should NOT try and get a refund. If the user's actions caused you to NOT be able to see the movie, event he next day, then you are entitled to a refund. Listen to your heart; I believe that all people have a good one, and it can tell you right from wrong. Besides, karma is a real, and it WILL get you! :)