The NBA is more concerned with growing world wide and teams like the Charlotte Bobcats, while important to their individual markets, are simply inventory to spread the game globally, not necessarily to dominate a particular market.
Basically, It doesn’t matter where the team plays to the upper levels of the NBA. New York, Los Angeles and Chicago, maybe but the rest, it doesn’t matter where they are. As long as a city can put up an arena, somewhat sustain a bit of TV or local business revenue, the league will use whoever and wherever to stock its shelves with content to send out into the world.
It used to be there was a building in a town that hosted the circus, a couple car shows, maybe wrestling a couple times a year and the main tenant would be a basketball team. They sold tickets and kept the lights on to support this local building. It evolved into it’s own beast, certainly under David Stern where places that never had a major league team of any kind, suddenly had Michael Jordan visiting 4 times a year.