I think it will grow as long as old racers continue to bring out their kids and show them the fun and learning that can be had with racing. Certain areas are just not feasible to have a track, and that is why the tracks are popping up outside of the cities. I feel very fortunate to have a local carpet track that is located in the city and open 24/7 for members.
Support your local shops, and you will see the track population grow.