consumer behavior psychology stuff is why ESPN doesn't simply build everybody else up and try to discredit the Big 10 in football. It is a tricky dance with properties like Ohio St, Michigan, and I guess Penn St, but the others can just be piled on.
ESPN has now owned pretty much everybody else for a while now. I supposed there is a business angle where if the other conferences are seen as inferior then maybe they won't have to pay as much but is it not better to build up all then squeeze the advertisers?