I can't believe the amount of misinformation on here. It makes me think for all the access work colleges do, it still isn't getting through. I don't know what more can be done - it's almost like people want to think the worst in Oxbridge before really finding out about it. Judging the students on a few you meet at open day, would you do that to any other university?
The majority of students are from state schools. So the majority of students are just like you. And I say the majority because even private school educated students are not some separate species. I just can't believe people write off students on first impressions, just because of where their parents chose to educate them. I'm not saying there aren't self centred, arrogant people. But they are just as likely to exist as at other universities.
In fact often at Oxbridge you're more likely to find people you get on with from the get go. On your first day in college you could meet some 100 other freshers, and I guarantee 99 of them aren't all public school "toffs". Compare to another uni where you live in halls and get to know the people in your flat, maybe some more on other floors and the people on your course. You could easily end up living with people from a background different to yours, and feel alienated.
I say all this as someone who graduated from Oxford within the past few years. There is so much financial help there for students, and increasingly for those who just miss out on the maximum grants. Endowments of college allow for subsidised food and accommodation. You can live out if you want - it's only in first year that virtually all colleges require you to live in. Terms are 8 weeks long - I don't know anyone who didn't manage to find work in the vacations if they needed it.
I don't know how access teams in colleges keep going - I am in total admiration of them. People seemingly don't want to listen to the fact Oxbridge are trying to show how no matter your social background, you still have a shot and you will more than likely fit in.
Final point - not sure if I made it clear but there's no segregation between private and state school students once there anyway.