Not to mention that 'lower memory usage' is only one of many benefits and, at least before the prices went mad, hardly the most important one on the list.
Practically speaking most people would want a GUI though.
Sure - what I mean is that being able to run an equivalent GUI to Windows (Gnome, KDE) using less memory than Windows requires is a benefit, but not the most important one to me. There are other bigger benefits to using Linux+GUI instead of Windows than saving on a bit of RAM.