Add a Where's Waldwarf or a find the hidden object to a quest series.
What do you think?
This could be a store item that inserts hidden objects lists into quest objectives for xp, loot, or just for fun.
You could buy/sell the search and find option in the store by adventure pack.
If I needed to find 5 hidden stars, four fruits and two kobolds for bonus xp or end reward loot boosts, it could make repeating a chain more enjoyable.