I would think that it is from the success of the GMs efforts to eliminate certain toons that automatically obtain a lot of materials in their travels from Point A to Point B, and repeat 10,000,000 times.
Maybe people are hoarding so they'll have enough to craft S80 weapons.
Even if every lvl 80 was doing that, you wouldn't see much of a difference in the market.
I don't know. Most of the people that will be able to use S80 weapons will also want them to glow nicely. Unless they use BEWS that will mean crafting a lot of extra S80 weapons. AFAIK S80 weapons require 5X to 10X the mats of the S weapons [2000+ mithril alloy for example].
Not that no one will do it, but you'd have to be 100% out of YOUR MIND to consider blowing up S80 anything.
The other night someone blew up a +12 drac bow trying to have it go to 13. Yeah. Who was it again? They were talking about it over Hero chat. It seems there are people who want to see if they can get something to +22 S grade.
(Is that rumor even true? I heard that the highest +sed up weapon in Korea is a +22 drac bow.)