Nobody wants them, except for those who know how to use them. Even in RL you only need to go back a couople of hundred of years, and mankind didn't know any particular use for most of the elements in the periodic table (which itself wasn't yet invented). Nowadays, with the great advances in science and technology, great many elements are processed by industries and used to make our everyday lives easier. Just something as commonplace as stainless steel isn't yet 200 years old. Chromium was of limited interest in the past, only useful for things like pigments (like great many other substances), which didn't really require a whole lot thought behind its use.