Exactly. They were making themselves into a political family. Daddy tried to run for Senate and failed, so Josh was being groomed for it. The deception and attempts to sweep it all under the rug tie in more to Jim Bob’s political aspirations for the family than they do to the show. The show was useful for name recognition and generated some sizable income, but the politics were the most important thing.
My take anyway.
And their “base” would be their many true-believing viewers; fellow ATI members of the Gothard Cult; and all those Quiverfull followers. I wouldn’t be surprised if Josh had planned to run once he turned 30.