The NYTimes review of Blue Crush has an interesting thought, though maybe I've just missed it from other sources...

The movie is also the latest example of a subgenre that might be called feminexploitation. (Earlier examples include "Bring It On" and "Charlie's Angels.") The idea is to find heroines who are strong, tough, capable and resilient, but who also look fabulous in bathing suits and other revealing attire. The audience appeal is theoretically universal. You can ogle Anne Marie and her friends or you can aspire to be just like them, or even a little of both.

I'd say the camera and script of BC were a bit more respectful, though the marketing wasn't.