I have a feeling that this is a case of "someone at Adobe screwed up, but the horse has left the barn, so they have to live with it."
I'd happily pay a few hundred bucks for unsupported, non-current versions of CS (with that figure getting progressively smaller the further back in version history we go). Adobe's current sales model is completely impractical for non-professionals who want to get their feet wet. They have the "elements" line at the low end and CS at the high-end, but nothing mid-range. I think that older versions of CS would be good mid-range products.
I'm reminded of the immortal Onion headline: "Photoshop Actually Bought"