Yeah, I have to agree with this. It's only a one time thing and yet even if you do all of them they don't give you enough XP for a single job. That's definitely rather poor. As it is, it really does feel like you're almost punished for doing side quests when just spamming FATEs in the same zone is more rewarding given that they not only give you more XP but they also give you Gems as well.