Thanks for your comment! The idea here is that you get bonus EXP for returning the statuette. You can think of it that way: the priests, who wanted it back, mostly stay in the temple and rarely talk to others, and common people weren't that interested in the artifact. But the other (probably bigger) reason is, I wanted to have some variety with quest rewards, so this one gives more EXP, while several other quests where you help the common folks can raise your Renown (I don't know if you've run into them, as sidequests are randomised and you don't see them all in a single playthrough).