You may not realize it, but flight attendants are basically the airplane equivalent of those rhesus monkeys NASA used to launch into space. As they take your crap with big, fake smiles on their faces, you might notice that those faces are flushed and sweaty because flight attendants are very likely to get sick. In fact, their health is so poor that the Centers for Disease Control and Prevention actually has an entire program that examines and evaluates flight crews for things like infectious diseases, mold and the constant barrage of cosmic radiation that affects every flight (most of us don't fly enough to be affected by it).
"We figure we've got around a 30 percent shot at getting superpowers."
Honestly, how many of you have a job so crappy that scientists study you to determine the experimental mystery diseases you might catch just by showing up for work? And to be clear, this isn't just a preventative measure in case something happens in the future -- most flight attendants rate their physical health from "fair" to "poor." Being packed into an airtight tube with 200 other people every day will make you sick.