Back when they first started the "Buy a large popcorn and get unlimited refills" thing at the movie theater, I would simply save my bag from previous movies, wi

Back when they first started the "Buy a large popcorn and get unlimited refills" thing at the movie theater, I would simply save my bag from previous movies, wipe them down and bring them back the next time. Unfortunately, they changed it to "1 free refill" and then even amended "Same day only" to the promotion. So I stopped doing it at that point. I don't mind hacking the system if I can figure out a way to technically follow all the rules.