We also use fashion as a sort of protection, or armor. We have power suits, favorite black pants, a special shirt--something that flatters or boosts our confidence or makes us feel powerful or safe.
As far as preferring name brands or not, I like both. What matters most is the comfort (physical and psychological) of the clothes. When I find a name brand I like, I look for other things from that same line, because they're likely to have something in common--the fit, the fabric, the style, the attitude.
Fashion has evolved in the past hundred years just as it has over time--as our culture and attitudes change, fashion comes along with it. One thing I find interesting is that as women's socioeconomic status has evolved in society, the fashion industry has become less able to dictate to women what to wear. Fashion still changes, and there is still a strong interest in following trends and looking of the moment--but it's considerably less important than it once was, and the prevailing sensibility now seems to be "I know this look flatters me, and I will continue to wear it regardless of whether or not this particular skirt length is considered "in" this year or not. I think women are still place a lot of value on knowing what's "in," but are less concerned with actually wearing it--we want fashion to fit our lives instead of the other way around.