One customer has a trick for getting free movie theater treats, and you're not going to like it one bit. I wish I'd never heard of such a foul life hack. But here we are. There are plenty of ways to sneak food into movie theaters . In fact, as some older generations have pointed out in discussions of the topic, theaters used to actually police what you brought in. They used to make you throw out the candy stuffed into your mom's purse. These days, the employees mainly check bags for safety purp…