Fashion Industry Affects Our Lives

I've noticed that my girlfriend tries to keep the track of all the modern fashion trends and she spends pretty much time on that. You know, it's rather hard to track all those "important" events of the fashion world and I don't understand why some people, especially my GF, spends so much time on such thing.
I found a pretty interesting article about fashion industry and its impact on our lives. But I don't think I can agree with all the statements that fashion website has. For me fashion is a way to look nice for people surrounding me, but some people give too much attention to it. At least I think so. I can't understand the fact, that some people spend thousands of dollars on the jeans or t-shirts they can buy for several dollars :)