I honestly do not have a lot of direct, first-hand experiences with other racial, religious, LGBT, socio-economic and/or other groups on campus. Really, the only times that I see these types of groups is when they set up booths at Red Square and do "tabling" which is where they advertise for their clubs or perhaps a certain event or cause that they're sponsoring.
I honestly think that all students can find their place at school. UW has over 600 clubs for students to join and find their niche, and these clubs include ethnical, religious, sexual orientations, academics, athletics, and various other interests. There are a lot of programs and sessions for scholarships for students who feel the strain of tuition, and although budget cuts are taking a lot of things away, I think the UW is trying to do its best to cater to as many students as possible.
Seattle is often a cold, blustery place, so North Face is everywhere-- vests, jackets, raincoats, backpacks, you name it. It's everywhere and it's worth it, so invest in one. I have three coats and a backpack myself. Jeans and Ugg boots are popular as well amongst girls, and jeans and sneakers are what guys wear. Frat and sorority members are more obvious on campus since they all dress alike-- "bros" wear basketball shorts, crewneck sweatshirts, backwards caps, and socks with slippers--even when it's raining. You might see them wear suits as well since a lot of them try and go into the business school. Sorority girls tend to wear crewneck sweatshirts with lululemon yoga pants tucked into Uggs with their make-up done but hair up in a bun held back by a headband. These might sound scarily specific but that's really how alike they all seem. This is a generalization, but it's about 75{4a082faed443b016e84c6ea63012b481c58f64867aa2dc62fff66e22ad7dff6c} true. There's always an exception, but I wouldn't know since they probably look like everyone else.
I would say different types of students interact. This isn't high school anymore. Granted, I feel that the Greeks tend to keep to themselves, but otherwise, people are more interested in actually maintaining a meaningful conversation rather than being friends with "cool" kids. Considering the fact that UW has a student population of 40-something thousand, no one is considered popular. Sure, we know our athletes names, but honestly, I walked by Chris Polk yesterday and had no clue until my boyfriend told me. So there you go.
A lot of students are in-state, but increasingly we've been getting a lot more international students-- China, Korea, Japan, Australia, England, Germany, all over-- and more students from out-of-state as well: particularly from California, but also some from the east coast as well. A few mid-westerners, but mostly people from Oregon and California.
In terms of what financial backgrounds are most prevalent, there is a wide variety, although I don't know the exact background. What UW is great about is that it acknowledges all financial backgrounds--it has a program called the Husky Promise in which it gives full scholarships to students who qualify, for all four years. It's a great program that was started by our previous President, and the program does a great job at getting its name out there and being visible for people to contribute to.
Students are politically aware but I don't know about active. We've certainly tried to be, especially when it comes to lobbying Olympia. Our ASUW is great about encouraging participation. Most people at UW are predominantly left-- Seattle in general is fairly liberal-- but the campus is respectful of people's beliefs regardless. We have an active UW Republican club, and the Republican and Democrat clubs enjoy getting together to debate.