Ba'ku

The Ba'ku are a bunch of nauseating, self-righteous, technology-hating Wholesome Small-Town Folksy People in Star Trek: Insurrection. They inhabit a planet of the same name in an area of space known as the Briar Patch, where abundant metaphasic radiation allows them to live care-free lives, frees them from the burden of disease, and grants makes them ageless. Yet they apparently didn't feel the need to share their great discovery with the rest of the Alpha Quadrant.

At one point, a group of them wanted to leave the planet. We learn that this group tried to take over, but they were expelled and became the Son'a. This doesn't make much sense. If they want to leave, why start a revolt or coup? Why not just leave? Did the village leaders have control over the only starship on the planet?