Force your guests to work for food
You're already putting so much effort into making sure your guests have a horrible time, so why should they get to kick back and suffer through the evening without giving anything back in return? Try giving Uncle Hank your calculus homework and give grandma that broken iPod that hasn't been working since 2010. She doesn't know anything about how to fix electronics??? Tell her that's unacceptable! She already lived through the Depression; this should be a cinch compared to that.