Who are you or I to say what someone can ask for coral. If the price is to high, no one will buy it.
Most people are trying to offset the high costs of this hobby by selling a few frags here and there. If they buy nice stuff, should they sell it cheap b/c we don't want to pay that price?
If I buy a boat, is it fair to ask my friends to pay for some gas when I take them out fishing?
I have some nice stuff, and some not so nice stuff, my for sale prices range depending on the piece. Should I sell everything cheap b/c people on MR don't want to pay what is a fair market price?
I have tried to sell a large coral for $20, and not had one PM, then I mark it as "free" and I get 30 PM's in 30 minutes. I have had equipment at reasonable prices, and no one sends a PM, I took off 8% ($20) and I got 11 PM's in less than an hour.
Everyone is within their right to charge what ever they want for coral/fish/livestock...it will only move if the price is reasonable, or in fact, cheap as MR is cheap.
There are only a few people on this site charging crazy amounts (This only applies to non-vendors), and I agree they are scummy, but it's within their rights to do so. AND, furthermore, you should be happy you live in a country that allows them to do so, and gives you the right to say "no" and shop around!
Then again, some people are just weasels
