He's smiling because he knows the secret. The secret of why we must eat Flex Seal. We must eat it, and that is the secret. The secret of the powers it gives you. The ones that you knew weren't possible. The ones no one would ever believe. The secret powers. He smiles because he can't tell you. No one can tell you. He smiles because he knows. And you won't know. Not until you eat Flex Seal. He smiles because he knows you won't. He smiles because he knows you will never know.