I think part of the reason for it's rarity is the fact that it just isn't that popular. If there were greater demand for it, it would be made more readily available. It's just a different shade of red/purple than #8, not any harder to produce (most likely). The reality is, that color just doesn't go with many things. That is why it is rare, that is why we've never actually seen a picture of the shoes on someone's feet.
I do think it would look good in a casual setting, and I'm sure someone out there bought them to wear them, but color 8/cigar/black and even ravello/whiskey are just much more versatile than #2.