I think everybody is missing two important points. Other timeshares, if bought from the seller, go for ten times what they can be purchased for from a re-sale. I see timeshares that someone paid $25,000 for selling for a few a hundred dollars. There is no ROFR there, so the shares fall to what the market demands.
Disney is different in 2 regards: first, the deed is not in perpetuity. It would seem that a
DVC deed that has only a few years left will not go for as high a price. $17,000 for 160 points that last only 10 years amortize to a pretty penny per year!
Second, Disney retains ROFR. This keeps the price up, perhaps artificially. Suppose Disney changes this policy, or lowers what they'll accept? Prices would quickly go down.