Or, let's take the San Francisco Bay area, which has several thousand martial arts schools. Would it really be practical to establish 500-600 profitable fencing schools there? We're pretty far short of that mark at the moment. The same could be said of pretty much any major metro area in the USA.
Suffice it to say, I think that no amount of entrepreneurial initiative would be sufficient to create a 7-1 martial arts/fencing school ratio in virtually any part of the US. Even a 70-1 ratio might be pushing it, in most places.