It's all about supply and demand
Supply and demand, and - sadly - VASTLY hyped fads based on nearly insignificant differences in coloration, and/or internet bragging rights.
6 or 7 years ago, I bought a scoly similar to the first one in this thread for my 125. Really pale blue on a mostly red background. Maybe 4" across. I think I paid like $50 for it at TRS or something. I remember they had a bunch of similar corals, all in the $40 - $80 price range. These days, you can't even touch the average-looking ones for under $100, because suddenly some "cool" ones appeared and now the entire market is through the roof. Of course, the fans will claim that there's no way possible the coral I had was anything like these new popular corals, because they've all been discovered on some little knoll no one collected from before, but to the non-fad-influenced eye, I don't see the difference.
Same thing with Chalices. I had an average-looking one in that tank, and no one would drive all the way out to my house in the boonies for frags, even if they were free. These days, little 1" slivers of similar corals are $50 - $100 and people can't buy them fast enough.
I guess I'm just venting because it ****es me off when a type of coral I like suddenly becomes popular, because the prices go through the roof for no reason and I can't justify buying them any more.

I will not dispute that corals like the ones in this thread are beautiful, but I also think the prices are not justified.