Aeropostale really isn't that expensive. .__.
American Eagle and Hollister are expensive for what they are. A tank top, twenty bucks? The tank top probably cost five dollars to make. It's because you're paying for their label. It's the same thing if you buy Converse or Nikes. There label is worth money, and it looks good if you wear it.
But really, it isn't all that bad. At Hot Topic, it's about twenty dollars for a t-shirt. I've gotten shirts at Aeropostale for ten.
I own a few shirts from Hollister, but I got them like two or three years ago. The trick is to go to the back of the store, where they keep the clearence items.
American Eagle isn't that bad either, depending on what you buy. I hate how the shredded denim mini skirts are thirty to fourty dollars, but everything else is just a bit on the expensive side, not outrageous, in my opinion.
Abercrombie is the most outrageous out of the four, if you ask me.
I used to shop at those places, but I don't really shop their anymore. My godmother usually gets me clothes from AE for my birthday/Christmas, etc, and I appriciate it a lot more than I used to, just because I don't shop their anymore. I shop at Hot Topic and PacSun, and they're just as expensive.
So I don't think it's fair to pin the prices just on the 'preppy' stores. Clothes are expensive these days.
I have heard about Plato's Closet though - they sell these brands of clothing, for way less, because someone bought them at full price and wore it once (Or sometimes didn't even wear it. ._.) and took it there. I've personally never shopped there, but I've been wanting to, because I've heard the clothes are very high quality - they look new; no stains, holes, etc.