I prefer the GMT; but, for me it is a tool. I keep the main dial set to local time, the GMT hand set to the office (London), and the bezel set to home (Was Chico CA, now it is SLC UT) so I know when to call my wife.
The facts are, I can not see this as being a feature that is at all useful to very many people. Yes, carrying a second watch in the pocket, like some of the people I work with do, works; but, I like having all the timezones laid out on my watch.
If I had a normal job (oh how I dream of having a normal job) I doubt I would have multi time zones. GMT watches are entirely unheard of in China because China only has one time zone. As such it is a pretty uncommon feature.
I would suspect that form most other people there are not many other timezones, that are not so local that it is easy to remember, that really matter to them. If it isn't useful then it is unnecessary clutter.