Agreed. I went to DePaul for my undergrad in Philosophy and found it a perfectly pleasant and interesting place to be, particularly if you want to study continental philosophy. I think it would be rather difficult to find a university where the majority of people, both at an undergraduate and graduate level, aren't "mainstream" because, well, that's commonly how mainstream culture works. I think you can (and will) find pockets of interesting, artsy, and/or counter-cultural individuals anywhere you go (as I did at DePaul).
To the OP- if you have questions about DePaul, feel free to PM me. Most of my knowledge comes from being an undergraduate in the program though.