Imagine looking all directions and seeing no enemy ships before stopping by this island. You step foot there and start to Shovel the ground. You then place seeds in the ground. You use buckets of water or rain to let these spots grow. You now have fruits and vegetables to either eat or sell to one of the merchants. Those who want to take the tome can chill on one island while growing crops in order to sell the goods. Some may not like it. Some may love it.
Another way this could be implemented is to find either find an island with a plot to grow things or only one “plot” can be placed per crew that they could place on their ship.
Imagine using the alt click or LT to feed a berry to a pig, the pig now follows you, you can pick it up and put it on your boat. You now have a pet.