What infrastructure are you refering too? Do we have the capabiity to build numerous large outdoor tracks? Yes we do, but those that have the $$$ decide to do many other (less risky) things with it.

I am not sure about the part of the world your in, but here in the U.S., we only have the population density needed in a few areas. Most of the country is very spread out. And those in the spread out areas tend to things like hunt, fish, race real cars, ski, play online games ect. RC car racing is predominately a middle class hobby here, rich folks have better things to do. So with lots of things competing for every dollar in
your pocket, rc takes a hit.

In addition to that, having an rc track is an insurance nightmare over here. Drivers stand; dangerous, heavy electrical network; dangerous, small cars hauling ass at turnmarshals just standing on the track; dangerous. And thats not to mention a nitro track that OSHA might get their fingers into. God forbit you spill some fuel.

Its not as easy as it seams, thats why most tracks, for TC anyway, are indoor and smaller, they can bring people in year round regardless of weather.

If you look at the very few places we have asphalt tracks, they are in areas of higher population density and still dont have the numbers of their European/Asian counterparts.