Surely you're not implying that every person with a PhD in something is an excellent practitioner of that thing. Most aren't. They shouldn't be - their job is primarily research on that thing, and teaching that thing.

Not every finance professor can manage a multi-billion dollar budget, not every Political Science professor can manage a campaign or run for office, not every Comp Sci professor can maintain a university network, etc. Not to mention the fact that not every college will even have a professor for every discipline that you could theoretically use to replace an administrator.