Veganism
Due to the abundance of vegetable foodstuff it's entirely possible to play the game with a vegetarian or vegan blockhead. There's no need to kill creatures for food.
Leather and fur can be scavenged from dropbears and donkeys that die of natural causes, or obtained via meditation or from a trade portal, so a blockhead can still make leather and fur items, albeit slowly. Dodo feathers for making the Tyrian Purple pigment or a soft bed can be acquired the same way. However, shark jaws can only be obtained by killing a shark, making it somewhat more difficult to obtain. Poison can only obtained by killing a scorpion or via a trade portal.
Uses
While veganism or vegetarianism in the game has no useful function or value, it can be seen as an additional play factor or as a challenge for more experienced players. While a vegan character may wish to solely farm fruits and vegetables, a vegetarian player could, in addition, keep dodos for the consumption of their eggs.