That's a tough one. I am a little on the super-frugal side (our heat is set at 62 right now...mmmm....toasty), but I have also gotten very set on the "I live like an adult now, thank you" lifestyle. Cornell has a major one-up on Duke only because I like being a homeowner and can't stand the idea of being a renter again. Being a renter with roomies? Ugh.
But I will say that you aren't going to spend a lot of time at home, so chances are good that you won't run into the person much. Also, it's really common in Ithaca for people to get housemates and be pretty choosy. Interviewing is definitely normal and ok. I often see posted notices like this:
We are: two fun womyn and a cat, nonsmokers, vegan.
You are: queer-friendly vegetarian or vegan who is looking for holistic community living experience.
High speed internet included.
I'm not kidding.