There comes a time in the game when collectibles become unwanted as you have so many already in store, so the twice daily collectible drop is ignored and unwanted by many higher level players.
Personally I can't resist hunting them and cleaning my island, but also as they can often be used in trade.
My game suggestion however is a final reward for collecting them all and completing the quest..maybe a special buff or an extra gem for each full collection, maybe a point for each full collection that can be built up and spent in store? Just needs an incentive to do the hunt.