Could also be that desert land and transportation are both dirt cheap.
Desert land is cheaper. In my initial scenario in the first post, envision MoonShadow's home to be on a desert plot. As for transportation, is $800 cheap to transport a sixteen foot skin that is part of an aileron, so that it can be treated with a coating?
I paid $450 to transport my six foot tal Sonic Championship arcade cabinet, and that was on a truck with other shipments, too, so that sounds cheap, yeah.
It's also likely cheaper than the costs the company would've had to deal with if it built near other people if zoning laws didn't exist.
You're only guessing. The bottom line is, you don't know the reason they're out there in the desert. The real point here is that you can't really predict where a company may choose to locate, and in the absence of regulations, you can't really assume that a company will choose to do one thing or another.
Regarding the $800 shipping costs, consider that the aileron skin is probably about 32 square feet. An airliner's wing, including top and bottom. will likely have 2,000 square feet. There are two wings. That's 4,000 square feet. Of course, for all I know, some components may be batch shipped, others not shipped at all - I won't claim to know, but what I've observed.
Of course, you pay for this when you fly. The real cost is fuel. A 747's tanks hold 57,000 gallons, and that will take you across the Pacific. A bit off topic, I realize, but interesting anyway.