The Big Ten network has no hope of getting on basic cable in the NYC market without a local team. Even if they can't sell it in NYC at first, just getting on basic cable in New Jersey is big money. There are almost 9 million people in New Jersey.
Maybe NYC will never "get" college football, like it never really got NASCAR, meth or Garth Brooks. But if it does, there are many many millions of dollars to be had. That's what lies in the calculations.