How can you say this with a straight face? Here's the average price on Leviathan for magian trial items for the most popular trials:
Strength (fire)
Flame Geode: 70k
Ifritite: 1k
Evasion (wind) <- note that most people make 2 of these for dual wielding jobs (THF, NIN, DNC)
Breeze Geode: 20k
Garudite: 20k
Are you seriously trying to imply that the Goldsmiths are screwing over people who are working on fire trials? If that's the case, maybe something should be done to alleviate this. However, I think whoever gave you this information is full of shit.
As others have noted, the Cure Potency trial is the only light trial being done (Light Geodes 10-20k, Carbites 1k), and only crazy people like myself who are serious about their mage jobs do the dark damage and/or accuracy trials (I did both, 1k for each item). As it stands now, I can't justify finishing off the fire damage staff I started before I took a break last year because the cost of obtaining geodes just isn't worth it, considering how infrequently I focus on using fire spells.