Because HIV and Hep C don't kill you instantly. But you will die. Until that point when the meds to extend your life no longer help you or when the complications from those meds take a toll on your fledgling health, your life is miserable. Does that answer your question regarding the statistical comparison? All dangerous jobs have safety precautions to try to minimize danger as much as possible. I don't understand why it boggles your mind that people in the porn industry would want the same thing.