Paul - I mentioned this in a comment below - most women can't choose just the cheapest pill. With negative side effects, or a health issue like Endometriosis or Polycystic Ovarian Syndrome, require women to try multiple types of pills that work best for their individual problem. I can't use the cheap $9 pill because I have PCOS - the only pill that works for keeping my symptoms in check is an expensive $50 brand. In short the pill isn't just about not getting pregnant, it's a medicine for health problems.