One final thought on why folks work for colleges and universities. It's probably not particularly insightful, given the distinctive role higher ed plays in our society, and the even more exceptionalistic view many of us take about our workplaces. Never the less, it strikes me that there's a fair amount of conflation of what we do with where we do it.
Personally, when I came to work at Greenback, the duties I took on weren't much different from what I had been doing in private industry. And when the sustainabiltiy opportunity came along, my attitude was more one of "yeah, I'm probably the right person to do that" than "ooh! ooh! That's what I've always wanted to do!!" The more I've learned about sustainability issues and concerns over the years, the more I'm committed to doing as much as I can to address the problem set, but the truth is that I've been addressing problem sets my whole career -- this is the biggest, most complex one I've ever tackled (of course), but it has many aspects in common with other things I've done.
For many of us who are staff (employees for whom neither teaching nor research is the primary assignment), a college or university is pretty much just another employer. That's particularly the case for those of us who've worked in other industries, other sectors of the economy. In my case, working at Greenback has a number of advantages, but I could do similar work (and provide similar benefit to society) on another campus, or even in another industry. Like an accountant or a plumber, my skillset transfers fairly easily. (Or, at least, I like to tell myself it does.)
It seems that for many other folks, their vision of their skillset is limited to higher education, and maybe even to their particular campus. With the national economy as slow as it is, maybe they're not doing their careers any harm at all. On the other hand, I'm not sure that there's an upside, either. Unless you count the "halo effect" of associating with your favorite college or university.