You don't take your cat with you to go bird shopping. Not because the cat isn't polite, but because he's a cat.
Good heavens, I suppose a man may eat his own muffins in his own garden. " "But you have just said it was perfectly heartless to eat muffins!" "I said it was perfectly heartless of YOU under the circumstances. That is a very different thing. " "That may be, but the muffins are the same!