Use Less Water for landscaping

WHY do people insist on landscaping with grasses that are not native to the area? The west especially in the desert should not have lush, green lawns, it uses so much water...

I'm looking into groundcovers that will work for our backyard, when we moved in the backyard was compacted dirt unsuitable for anything to grow, now that it's spring and the ground is wet, it's possible to plant something.

Here are some links to groundcover information.

http://www.entomology.cornell.edu/Extension/Woodys/CUGroundCoverSite/GroundcoverMain.html