They only eat GRASS.
Game of Thrones Season 2, Episode 9
Have you seen
Leaves of Grass?
Breaking Bad Season 5, Episode 9
Why can't the GRASS
always be greener on your side?
Breaking Bad Season 2, Episode 10
Khaleesi of the Great Grass Sea,
Game of Thrones Season 4, Episode 10
Put artificial GRASS in my backyard,
The Big Bang Theory Season 10, Episode 22