NHS waste

Why is the NHS broadcasting television adverts (in the middle of a highly watched show like the Simpsons, of all things) for a free cervical cancer jab for female year eight students given that they're going to get them whether they ask for them or not? What is the point of it? Am I missing something or is this just a collossal waste of taxpayers' money which could have been spent on, say, cleaning the wards, or several extra nurses? Or if they don't care for such things, a reduction in the national debt, or tax cuts...