Kinda like the other bonuses, this would apply for unused shrines in an adventure.
Spendthrift: 7% XP Bonus
Resourceful: 15% XP Bonus
Crafty: 25% XP Bonus
Naturally, some quests wouldn't have this bonus, while others (Like Coalescence Chamber) that only has one Shrine for a very long quest, might give the Crafty Bonus outright.