I was actually very surprised to see this too, and i was looking forward to seeing the finished "Sandman" piece. I think it's sort of unfair, or at least a little awkward, that there was a thread about it, to which many members contributed, and now the final piece is only viewable with a subscription to the site.
I see now that this has been changed.
It isn't wrong for an artist to sell their work, however, when the piece is shown online, and the viewer gains to rights to use, sell, or do anything with the art they are viewing in the portfolio, it is no different from viewing it in an exhibition. When artists sell their work, they give all the rights to the buyer (for example, selling artwork to a game developer.)
It's obvious that everything cost money, but i think that with Kon's skill, commissions would cover costs for a domain (and server-space) completely. I run my own server out of an old machine that my family had lying around, and my domain name is one registered at a free domain site. I am really curious as to why the site went subscription based. A professional artist should be able to cover those petty cost with work done for commercial groups.
EDIT: also, for those of us without money (or a paypal account/credit card, for that matter) it is significantly harder to actually get a subscription. If i knew you and could hand you the money it would be no problem, but the hassle really isn't worth it, especially when the subscription is only to one artist's site.