Activities like FATEs, dungeons, raids, and select (soloable) quests should yield currency toward gear and crafting materials specific to their level range with an option convert them higher or lower at varied ratios.
I dont know why but this just really grinds my gears. I hate it when MMOS use multiple currencies instead of keeping it at drops. I know how it does make a more fair system but it doesn't make much sense and ruins the immersion/game a bit. Its because people wont be seeking that powerful item instead they want "FATE coins", they wont be hunting for powerful gear, they're collecting marks for gear from a shop, and to add it all up, all DAT currency D:
It keeps people playing the content instead of doing it once and never looking at it again though.
That, the implied fairness, and if we're really going to play the immersion card, then it's absolutely silly Big Nasty Mob of the Dungeon seems reborn every time you set foot into the area. Realistically, these mobs should either be one-time affairs or require some kind of birth/maturity cycle to promote the theme that mob has grown o nasty proportions, and if not allowed to grow, no drop for you~. Though, there's always the classic wondering why a monster is carrying a small armory. At least craft materials make sense if you turn its horn into a spear or something.
Silly tangent in mind, the ultimate point is that sometimes reality and immersion has to yield to player convenience. Sure, one could also hand wave and claim these shops are stocked by other adventurers/NPCs that have no need for such things, but that's almost... too easy? How about a boat ride from one city to the other? Personally, I'd hope Eorzea is bigger than the equivalent of an RL city and suburbs, but we've got boats moving us around huge distances in moments instead of hours. Why? Because sitting on a digital boat with nothing to do will be @#%^ing boring. We can also run/walk forever without tiring, needing food, or going to the bathroom.
That said, I can understand the fear of currency glut, and that's partly why I proposed the conversion mechanic so you don't suddenly find yourself sitting on a bunch of virtual coins now useless to you because you outleveled an area or general gear quality outshines what it offers. Personally, I hate how mobs drop "finished products" in the form of equipment. It's a classic problem that these drops are almost always superior to anything crafters can produce. In turn, it trivalizes crafting and forces people into consumable markets if they're even worth making. I don't expect equipment drops to go away, though, if for any reason, people are too lazy to find a crafter who can make what they want out of an ingredient.
But yeah, fairness. Guy that goes 1/1 on Sword of a Thousand Truths isn't a better player than the one who's gone 0/50+. He's both lucky while the other is incredibly unlucky. Bluntly, if you can kill a challenging mob 5-10 times, you've proven your worth. Enjoy its loot. The concept people need to spend months at a time for a single item needs to die, especially if we're expected to utilize the class system and play more than one.