They're seen in every Flying pokèmon scene. It's supposed to be your pokèmon, but it's obviously a black bird. Plus, most cutscenes that watch the sky have real birds. And no. (most) People do not eat Miltank. (almost)Nobody's that heartless. It's made quite obvious that animals exist in the Pokèmon world. Not all, but some. Not most, but some, not none, but some. Get with the program little one.