The last time I was there I asked if the ranch was used for anything other than an access point to the springs. Mike was not there but his lady friend, who has the ranch near by, was. She said that ways back they figured that charging for entry to get to the springs provided for reasonable cash flow and hence there was no other activity at the ranch.
Personally I wondered how well they would do if they built a lodge there for overnight guests who prefer not to camp, assuming there was enough visitors who would take the option. When I asked how many visitors pass through there each year, I didn't get a straight answer. Would be simpler to calculate the revenue. However considering that he charges $10 overnight, that's already quite a premium especially that it's per person.