Urm your argument is pretty flawed
1) Worse economy? Since when? The ES is tested on the new WLTP system, not the old one that the GS was tested on.
2) It actually has more space than the GS in the back. It is like a limo and some people might want that sort of thing.
3) Also the materials aren't exactly cheap. The reviews are favourable. Lets not forget the GS has some pretty bad materials as well.
4) The Pound has dipped hence the prices....., not to mention inflation
Also, if you've driven a new LS, you would know that the thing is deadly quiet, more so than any other LS before it and on par with the competition