It's been a long time since I've read something that fits the term "floating abstraction" as well as what CWilliams is talking about. Apparently, all voters have to do is "vote" for the government to "provide a service" and it magically happens. I think he has been reading too much Rothbard. A government does not provide a service. It provides a system of laws to protect individual rights. Using his scenario, the govt. would have to pass a law creating his system of schools (or whatever other "service" he deems some group wants), and such law would have to be applied to everyone, as any objective law would. So his suggestion is outright contradictory: his voluntary service immediately becomes coercive.
CWilliams asserts "a Government's purpose is to protect the rights of its citizens" without providing any evidence as to why this is so or how it achieves its purpose, as if providing services is all that a government does, as if providing other voluntary services could possibly be within the purview of government action.