It seems to largely be a result of the professionalization of the administration; in ye olden days universities were largely self-run by the faculty, with Deans and Vice-Deans just being professors who moved up into that position, sometimes rotating in temporarily. Now there's a whole category of professional career administrators who jump school-to-school, roughly parallel to the executive-management class in private-sector organizations (and they expect salaries in the $200k-$600k range).
One of the most revealing pieces of this interview: ...the dark little secret about these [merit] grants. They do not create access to higher education for students who otherwise could not go.
Interesting - merit grants are not helpful for people who can't afford college? Doesn't that imply that people who can't afford college (mostly) lack merit?
Oops, politically incorrect thought.
It seems like there are a lot of people earning livings off of the University system who aren't educators or researchers. Maybe there's been a lot of growth in this sort of thing since the cheap-college days of yore?