Administrative bloat is a natural tendency of organizations. I am not entirely sure why, though I understand some of the drivers. Never-the-less, I have seen it in nearly every organization I have worked in or consulted for.
Even the best-run private companies still have this problem. To remain competitive, then, they have to come through every few years and wield the ax on these growing staffs, almost like trimming back a hedge that keeps trying to overgrow your house. I spent a depressing amount of time as a consultant helping them. It is uncomfortable, sometimes heartbreaking work, and one wonders the whole time why there is not some better way to keep staff in check. To my mind, there is a still a great academic work to be written on this topic some day.
The alternative, in organizations that can get away with it, is administrative bloat. Like, for example, in this public institution:
That staff adds up to an incredible billion dollars in administrative salaries, or nearly $21,000 a year per full-time student. And remember, if this is just salaries, the actual cost is much higher because they all need offices, supplies, travel, etc.