Their menu basically consists of expensive vegan
  hot-dogs and fairly generic sandwiches, which is
  a tough sell in Chicago when you have some very
  good food around for very cheap.

I live down the street and went there about twice a month since they opened, and what you're saying isn't accurate. Drew's wasn't competing with your usual hot dog shop or fast food. There is a gigantic and extremely popular vegetarian/vegan niche market in Chicago, and that's the market Drew's was competing in. The food really was excellent and although from the menu things may have sounded "generic" in reality they really were not.