The "professional" part of your assumption is being generous
. People who are are professional sellers of anything: 1 - actually end up selling their wares at some point; 2 - are in tune with and know how to read the market for their goods/services.
Trainplane3 nailed it on the head with his responses above.
1st rule in negotiating (he who has the most time typically has the upper hand) will determine which way the prices ultimately go. Until they need the sale more than the 1700%-2700% mark-up, we'll likely see them continue to hold out hope someone flush with cash caves to desperation.
In the meantime we can all look forward to the upcoming Limited Releases and the opportunity to get the larger versions of the same prints with metallic highlights for @$100. Excited to see how they look as all the upcoming ones have some great potential for the use of metallics.