In television series about vampires, when someone is unconscious and in need of mouth-to-mouth, and the vampire says that they cannot do it because they are not alive... it makes me want to throw things at the screen.

Seriously. They are TALKING. Clearly they are able to use their lungs to force air out their mouths. It really does not matter that they themselves do not absorb the oxygen they breathe in. In fact, that should make them even more ideal candidates, as the air they would force down someone else's lungs would be much richer in oxygen content.

Where oh where did this idea come from and why do people keep doing it to me?