I'm guilty of judging people on their clothes. However, I'm open to a range of clothing types. If you look like you just rolled out the bed and grabbed stuff off the ground, I'm gonna go ahead and assume you're not even trying.
How I dress is very important to me. I have fashionable work clothes for work, jeans and graphic tees for when I want to be really casual, and skirts with nice tops/dresses for when we go out.
I shop for nice clothes based on brand. I usually buy clothes at Express for that because I can't blow $150 every time I want a shirt. I just have way too many clothes. I do happily spend $200+ on jeans because I can't stand uncomfortable jeans. For casual things, I just buy whatever catches my eye. Some are brand name and some aren't.
I try to keep up with fashion, but tend to buy things that I think I'll be able to wear longer than one season. I think looking nice and up to date is good to do.
As for the heels issue - I CANNOT walk in flats. Like, I trip all over myself and look clumsy and awkward. I have some DC shoes that I can wear because of the grips, but any other flat shoe and I'm all over the place. I wear heels 95% of the time.