Sorry, I deleted my post because someone else posted at the same time a reasonable explanation - a rice substitute ( https://news.ycombinator.com/item?id=6029358 ). Thanks for adding information.

My original text:

"The arid, cool land that quinoa needs was plentiful, since little else could grow there. And thus far, that trait has made it difficult to grow elsewhere." (posted link)

"Protein content is very high for a cereal/pseudo-cereal (14% by mass), yet not as high as most beans and legumes." ( http://en.wikipedia.org/wiki/Quinoa )

I'm puzzled. Why not stick to beans, which are cheap and plentiful, and come in a wide variety of shapes and colors?