So, I did a search to see if there were any better prices on the sheets, and I noticed that most were advertised up front as being rayon (the rayon being made from bamboo). That led me to look up what rayon was made of, which was a learning experience! Then I noticed this article and got thoughtful.

Yeah, I guess this is the place to post... Like the previous poster, I was curious about the fact this is rayon made from bamboo. I found:

In early 2010, the U.S. Federal Trade Commission warned several retailers that six major manufacturers were falsely labeling rayon products as "bamboo", in order to appeal to environmentally conscious consumers. While rayon may be produced with bamboo as a raw material, and the two may be used for similar fabrics (though natural bamboo is not as smooth), rayon is so far removed from bamboo by chemical processing that the two are entirely separate.

- from the Wikipedia article on Rayon