It's not rebellion if everyone is doing it; IT'S CONFORMITY !
A good example is the way Cosmo forces young women to dress the exact same way.
Actually, the fashionista herd, from boutique to Wal-mart, 'designs' clothes which are marketed at almost all levels which essentially back young women into a corner: they wear what is available.
Essentially, the decisions are made long before a young lady approaches the clothing section because so little else is available.