I know a few providers that took the indy plunge. Very few stay an indy for long. There is a thought that everyone can do something better than their boss/MMS/PPS. The reality of running your own operation is more complicated than most people imagine.
First of all, not all providers are confident enough to become their own boss. There is a fear that the current clients will not sustain them. Just read the reviews and it is evident that we are a very picky bunch.
There is also the matter starting the business. Matters such as licensing, inspections and taxation are tough to grasp. All of this was already set up when the girl showed up to work at the spa. I know some guys think it is all cash business and not reported, but you can't run a place for long that way. The girl knows know how to provide a service, but not how to set up the business to sustain it.
Lastly, for them to be a "boss" they can't be a "worker" in their culture. They have greater aspirations to hire other providers and be a boss at their own spas. It takes time to build that network of workers and some do eventually open up their own spas. This is why it is rare to impossible for you to get a session with an established MMS. Providing is no longer their goal. Having multiple employees and even multiple spas is their focus so they can be a "big boss".