The items are also all things that were already-made. Most are either in-game assets that were locked behind old season events, or were in-game assets no long in use (like the Scion clothes or Cid's old outfit). They simply attached the models to an inventory item and packaged it up. (And people liked it, mostly!)

Aside from a handful of dyes/minions, the cash shop hasn't introduced anything that couldn't be obtained or seen in the game previously. Adding something completely new and locked to the shop goes against the spirit of it.

...though I'm surprised we can't get 2.0-2.55 relic glamours there. Maybe for the best.