Just look up any town that had a single large employer and what happened to those towns after that employer left. Small companies do not posses the same ability to impact an entire town of people and everyone who lives in it, even those that didn't work for the employer.

OK, I will grant you this one edge case. As for the other 99% of people, my point stands.

So the have power only when they cease to exist? That's an odd example to use.

They don't have to cease to exist. They can just choose to relocate or close that location because they're big enough to do that. Maybe extorting another town for tax breaks if they relocate there while they're at it.