I know this may sound weird but....
1) I hardly ever pay full price for clothing (with few key pieces aside). Clothing stores typically rotate every 2 weeks. By the time I really think about it, it is usually on sale or for a lesser price (not including impulse buys). Also, you don't necessarily have to buy Theory, Yves Saint Laurent, Chloe to feel pulled together. A cashmere turtleneck from somewhere else can be just as good as one by Theory.
2) I can't say the same for purses. There is a distinct difference in quality between a bag from Chloe, Balenciaga, Dior, Chanel, etc... than you get from something from let's say Banana Republic. The right bag and shoes can make me feel instantly put together, even if I am sporting (heaven forbid) my Juicy sweats. I can wear ripped jeans and a cotton top but with my spanking new Gauncho bag, I feel like a million bucks!
3) I love the ingenuity of a variety of bags. I may never wear a top with bright cherries with little smiley faces painted on them, but as a bag, I am willing to take more risks! Not to mention the bag can totally change an outfit too.
4) I have a sickness in which I am trying to fulfill this empty void in my soul with calf and goat leather (or credit to Soybean, human liver on a rope)...... but I prefer to think it's reasons 1-3.