Because people sense the machine they are trapped in, they want to read stories about that. The dystopia is a metaphor for the present day and that is a more interesting and imaginative way to communicate an idea than a lecture without any narrative or fantasy elements. Yes this is also used as programming and trauma-based mind control, but the desire and interest of audiences in a story like Hunger Games is not surprising to me at all. And most people who read that book or watched the movie identified with the work-slave fighting for her family and her freedom, not the elite slave-owners torturing their citizens.