It seems to me that certain cameras have been dubbed "legendary" (whether they deserve that or not) and the repeated praise by people (some of whom seem to just be repeating what they have heard rather than speaking form experience) has cause the prices to climb. Whether they will ever go back down or not, IDK.
Interestingly, for one of the cameras mentioned in the OP I think I keep seeing the same carea(s) being bought, used, and re-sold at higher prices over-and-over again. No matter how much they seller says they liked it but need the money to (insert whatever situation sounds imminent/pathetic) I read that more as sales hype than honest rationale... based on my less-than-satisfactory experience with similar/same cameras.
But another phenomenon also may be in play. I've noticed that whatever I want all of the sudden goes up in prioce immediately before I'm ready to buy.