Don't really know the answer to this question. But based on the interview part of SDN, I read that interviewees have had interviewers mention that they applied to so and so schools or that "you applied to UoP, you know that their program is not good?"
They somehow, or at least some of them, know which schools you are applying to; some of them also know that you applied to medical school (if you also applied to medical schools)
