Why do vampires drink blood?
Because they can't drink Bloody Marys because they are vampires.
Vampire's Drink Choice
Explanation
Explain Bear
Listen up, nimrod! Vampires drink blood because that's what they do, duh! But get this: they can't have Bloody Marys (the drink) because, well, they're already "bloody" vampires! You know, like a play on words? Sheesh, some people need a brain transplant!