In my opinion, different types people prefer different routes for server management. If you're in IT -- a lot of it depends on how you got where you are today, and your personal temprament.
I've found that people with more classical training in information technology (i.e. programming), tend to prefer CLI for server management, not to mention people who were in the industry back in the days of 8" floppy disks and accoustic couplers. That's not to say that there aren't industry professionals that don't prefer a GUI, and programmers who like managing their servers the old-school way, etc, but that's how it seems to skew.
The one exception being that there a few things you can't do in the GUI that you can only do in the CLI. Personally, I find that irritating. Also, unless your server is very badly in need of a refresh or underpowered for its job, the 'too much overhead on the GUI' excuse really doesn't hold much water.
Finally, I would like to say that I personally am for neither the CLI or the modern GUI; I want that waving around virtual reality stuff that Tom Cruise had in 'Minority Report'. Oh, and as an added caveat, apologies in advance if I duplicated the same response as someone else. I've been reading the comments while trying to troubleshoot an HP printer that suddenly decided to switch all the print menus to German, so I might have missed a comment or two.