Yeah, most of the Gil currently in circulation comes from players questing / Fating to 50.

Quests that only one Class can do.

Lazy quick fix:
Make gear unbreakable (Temp)> Raise the leve cap (Temp) > Allow more monsters to drop small amounts of gold(Maybe..)> allow more gold to flood into the economy > add good min/max level recipes for armor/food > More people pickup crafting > Materials for the recipes cannot be bought from NPCs > Farmers farm mats for Crafters > Crafters synthesize gear for Farmers > Simba sees Mufasa's face in the clouds