My older sister and her husband moved to Las Vegas from Pennsylvania about two years ago, and I visited them for the first time in March. I had always thought of Las Vegas as a human tragedy--that's what the strip is for, after all. But the Disneyfication of the strip, combined with the growth of the city itself (I almost wrote "the growth of the suburbs," but most of the seemingly suburban development is actually in the city), has made the human tragedy less obvious, and the environmental tragedy far more so.

It's the things you describe: the perpetual waterfalls outside of the housing developments, the golf courses, the lawns, the general existence of the place there in the desert. (And the sprawl! Every housing development is a pod full of culs-de-sac, and the streets are the size of major thoroughfares back east.) I kept noticing brand-new highway on-ramps that were cut by gulleys--the little rain that does fall tends to erode these right away, because desert plants can't grow fast enough to keep up with the earth-moving.

And somewhere, in the background, there's a 100-foot-high bathtub ring around Lake Mead, where you can see how much the water level behind the Hoover Dam has fallen...

Let's not forget that there's some self-selection going on here: by definition, the majority of people who move to Las Vegas are not horrified by the thought of moving to Las Vegas, which means that they don't care, or haven't thought about, any of this. And they're going to come for the water.