There aren't a lot of super right-wing radical religious people. You're more likely to find tree-huggers, tree-sitters, war-protesters, etc. It's very liberal here. The atmosphere is very LGBT friendly. While there are clusters of people--Asians, African Americans, Caucasians, Latinos, etc--people interact and cross racial boundaries. It's blended, which is nice.
A student who is very religious or very conservative might feel a little out of place. There are religious groups on campus, but not many, and not many conservative groups either. It's very "save the planet, save the trees, save Darfur, help the underprivileged!" The teachers are liberal, too, and mostly secular. Especially in physics a lot of people roll their eyes at the proponents of Intelligent Design or make jokes about it.
Most students wear whatever. There are definitely the "cool" kids, who were obviously the popular kids in high school, but mostly people wear jeans or slacks, or on hot days skirts and low-cut tops. Lots of flip-flops, though hiking those hills in flip-flops can be down-right dangerous. Most kids are pretty casual about what they wear.
Four tables at the dining hall--depends on which dining hall! College 9/10 has more Asians than any of the other colleges, and Oakes has more African Americans/Latinos. Of course people eat at different college dining halls, but if you go to either of those you're more likely to see ethnic groups. Crown is more white, but not exclusively.
A lot--at least a quarter--of students come from Southern California. A lot come from the Bay Area--San Francisco, and further north. There's definitely a blending of "So-Cal" and "Nor-Cal." There are definitely some Orange County people here. You can pick them out by how they dress--very movie-star-ish. Big sun glasses, fancy purses, skinny, tanned, waxed, etc. But certainly not all are like that.
I think the financial backgrounds are mostly middle class. I don't think there are a lot of students who come from either very poor or very rich families. It's rather homogeneous in that sense .
Students are VERY VERY politically aware and active. Lots of protests, lots of activities, lots of discussions--by the way, all the activities on campus are great. We have an amazing performing arts center, and lots and lots of sponsored events on various socio-political issues, every single week. You could spend your entire time here just seeing all of the events.
LEFT! LEFT! In the words of one teacher, "Professors here range in their views from Left, to Far Far Left."
Some, but not most, students talk about how much they'll earn. Students are well-aware they'll have to pay back their loans and such, but most are more concerned either with just graduating or with helping people, or doing what they want to do in life.