Because they're dead, silly!
There was once a great Mexican Magician. He was world-renowned for his incredible feats. His most famous act, though, was his vanishing act. He would count; uno dos and suddenly he would disappear without a tres.
They approach the bartender and the first says, "WAAAAAAAAAAAOOOOOOOOHHHHOOAAAAAUAUUUAUAAAAUAAUUUUAAAAAAOOOOOOOOOOOOOOOYYYAAAAAAAAOOOOOOOOOOOOEEEEEEEEEEEAAAAAAAAAAAOOOOOOOOOOUUUUUUUUUUUUUUU."
The second whale turns to him and says, "Frank, you're drunk."
but the reception was incredible!
Well that's a clean joke, right?
Root beer floats!