I'm a vegetarian who is supportive of hunting. If you are going to eat meat, hunting and butchering it yourself is by far the most ethical and environmentally sound method of obtaining flesh as food. I simply can't reason with someone who finds it OK to eat an animal, but sleeps with one on the foot of her bed, and rages when someone else hunts.

That said eating octopus and specifically the GPO is particularly unethical if you subscribe to intelligence being related to sentience. Additionally it appears that octpus legs contain brain cells, the part you eat is in part brain.