I'm just interested in what the percentage might be from a statistical nature. It certainly seems like a majority of buyers at least are flipping the book. (but who knows, that supposition could be wrong, especially with such a limited amount of statistical data visible, thus my wondering) Why shouldn't they? the return is worthwhile. I'm not trying to say no one should sell the book aftermarket, lol. People can do whatever they want with what they purchase.
What is a signed book worth? What someone will pay for it on the aftermarket or what YOU would pay for it? I guess that just depends on perspective.
I straddle the cusp. I would have paid purchase price and happily kept the book in my collection (in fact I almost did, but for the UK restriction and my inability to come up with my mates mailing address in the UK in time), but I'm not going to pay $1700 for a copy (or even $1200). For me, personally that is just not worth it. For some people it surely is. The production certainly is an extremely limited and highly in demand book that some think could be King's last S/L.