A single sale isn't indicative of a broader market. QS doesn't come up at all any more so if a person has been searching for a while and jumps on this one, that doesn't mean there are dozens of others that see such value in this game. So let's see if QS owners that are tired of the machine start to list them for 10K. More importantly, how many people would pay that?
Somehow, in the last few years, QS has risen above most (all but Star Gazer) of the other classic Sterns. It's a great game, no doubt, but there are a lot of great games from this era.