IMO
The supply and demand argument has flaws when applied to a hobby of living animals, after all we are not talking durable goods here. you can't buy an i phone, cut it in half and resell it after all
The problem as I see it is that some people buy a coral with the expectation that they will be able to grow it out, frag it and make money. The hobby/business
Example:
Hobbiest "A" sees a super blue wango tango on a vendors site for sale for 500$. They buy it expecting to be able to make two frags in less then a year and sell them for say 400$, make a profit, and still have their specimen. Many good hobbyist are very successful doing this.
The vendors know this mentality in the hobby, they also know when they sell they no longer become the sole distributor any more and are in a way selling the "patent rights" as well, and therefore know they can charge whatever they want for . Since they are a living organism tht is capable of reproducing - supply will always increase, so the window of big money sales is limited by time.
Hobbiest "B" who is kinda new, sees how the system works and wants in. They think that this is the way of things and buy in, expecting to make money off their hobby. They feed the price increases by thinking everyone is willing to pay this much.
This system has a natural built in positive feedback loop that ensures prices will always rise for certain corals. The day people started talking about "collector corals" is when the hobby changed forever. People expect collector items to appreciate in value!
Once you've been in the hobby long enough you see this happen again and again. Zoas, chalice, acans and now shrooms and torches.
I am not making any judgment nor being critical ... just an observation from someone who's been around a while...
expect to pay to play - if you want in on the name game collector corals