thing is, they have a motion capture studio. it costs money to hire actors and such, and they need to do so for every new emote. plus the time it takes for the graphic team to put the effects and the coders to code them in.
not to mention the time put into designing it.
ffxiv isn't a profitable enterprise atm. they can't afford to waste time on jewels when they are starving.
hell, there isn't an emote for getting on top of the chocobo when summoning it :P