I thought I saw somewhere that they intentionally were coded to drop nothing to not incentivise killing of dolphins.
I hope you're right! Save the dolphins!
Also, just picture this... You set out on the beautiful blue oceans of Minecraft in your trusty wooden boat. Suddenly, a majestic dolphin appears in the distance and begins gliding through the waves to get to you. As it nears the boat, a parade of other dolphins surface and swim beside you. What a thing of pure beauty...
These dolphins better be cool, because I think I might be expecting too much