Well, it was on a Wednesday, and I don't think that Wednesdays are that much better than Mondays. I went to several British Finals on a Wednesday, and they all had WAY more than 2000 people.
Even were it shown on live TV, the place would have been packed.
Maybe a diluted lineup would have had an effect, but realistically, would Woffinden and Lambert had that much of an effect at the NSS?
Back in the day, people attended as much for the occasion, as they did for the interest in who was riding...