I don't believe so.
It does probably have a little more affluent of a patient base. But you're still going to see patients from every socioeconomic background. Despite it's Streeterville location, it's still a major referral center for all over the city, so you'll see plenty of interesting cases. You still see gunshot wounds in the ER. You still get TB cases. You might even catch a Cubs player (or minor leaguer) in the OR during ortho. You'll probably do part of your medicine rotation at the VA west side, where every patient has COPD + (insert rare disease here). OB/Gyn is done at Prentice, the busiest birthing center in the Midwest. Peds rotations are done at Children's Memorial, where you will probably see more interesting cases than all but a few places in the country. And despite it's Lincoln Park location, it truly does cater to patients all over the city. At least 1/4 of my patients families there were Spanish-speaking only (which is probably nothing for a city like LA, but in Chicago, that's quite a bit).
If you're still concerned that you would like to devote more time to working with patients with less access to health care, there are a number of community health clinics that NU students run/volunteer at around the city.
It was a good place to train...glad I chose it.