Don't blame the parents. Blame a culture that salivates over large breasts, whether made by God or surgeons. Blame TV, videos, and websites that make it seem to a young girl as if this is the only standard of worth or beauty. Blame young men who will drop a girl if her breasts aren't big enough.
My daughter has an 18-year-old friend who is planning to get plastic surgery next year. Her parents are friends of mine, and I know that they have done everything they could to teach her that she is a worthwhile human being even if she is very modestly built. But her peers, her classmates, and the general society around her that displays breasts everywhere apparently make her feel she has no beauty apart from her chest.
And before you ask, yes, this is an intelligent, fairly attractive girl, a good student and athlete from a Christian family. She is saving up the money for the procedure herself.
Liberalism seeks to blame everyone and everything but the responsible party. Personally, I hold the parents and the young woman responsible - in that order.