I think that to make it viable the instructor owner, would have to be in or near a major population center. You have to have enough people who a serious lesson takers, and who are willing to spend the hourly rates.
One my old golf friends owns the only, non-golf course driving range in my town of 50,000 people. There are other towns of similar size within a 20 mile radius, but they have their own ranges. Several years ago, way before the current recession, I asked him how his annual membership thing at $400 for all the balls you can hit, was going. He said he had a grand total of 1 member! He also said that not only did his average customer not have $400, but they didn't have $40.00. I can imagine what's going on now. I could afford it, but I'm still cheap. One of our city owned courses has a nice two tiered practice area, shag area. Limit for safety sake is 220 yds. Most days, including weekends, there is nobody practicing. Maybe around 8 of us that are regulars.
I don't think Trackman is coming to my town anytime soon.