Ghoul country, up north? Maybe the MLA are pushed west, or they just want to stay far away from Barnaky's MWBOS. Just to show what I'm after, http://en.wikipedia.org/wiki/Las_Vegas,_Nevada. Now consider the MWBOS at the end of Tactics controlling http://www.fourpeasonline.com/images/map.gif.
And from the Barnaky ending at the wiki
Spoiler
without the required resources and firepower the Mutant Liberation Army is driven west
But seriously, I guess it's just cut content, making this post just wishful thinking.