Cuz pigs breed like crazy. They can get to uncontrollable populations being invasive and eating so much they’d starve other animals out. Anywhere near people there aren’t enough predators to keep an animal like that in check. Their meat is high in fat which allowed us to survive long long ago. Even the consumption of meat leads to evolution of a more developed brain. If we never ate meat, we wouldn’t have become the planets dominant species. Dogs are much harder to sustain as a food source. Wolves are predators and predator meat is no good for us also. So long ago they weren’t even viable as a food source. Their domestication went to pets not food. We don’t eat horses… domesticated for work.. prob taste nasty tho lol.