I don't give a hoot about popularity, but black shell doesn't give you the subtle color variations of #8, ravello, whiskey, etc. over time. I agree with "not as desirable".
I think the problem here is on this site black shoe in particular are not as popular. I on the other side like a good black shoe " though I have to admit don't wear nearly as much as my other shells". I have two pair black shells and like them allot