For the same reason that the OP had to write a long and well researched post, along with relatively significant financial expense. My body likes sleep, and for me, "willpower to get out of bed" isn't something that magically occurs at 8am. There are studies that associate willpower and self-control with blood sugar levels, exercise, and other factors, and I'm under the impression that people that naturally wake up in a dark room simply from the sound of an alarm clock have widely differing body chemistry from mine.