Guess they didn't really read the book.
On page 45 of Suzanne Collins's book, Katniss sees Rue for the first time:
…And most hauntingly, a twelve-year-old girl from District 11. She has dark brown skin and eyes, but other than that's she's very like Prim in size and demeanor…Later, she sees Thresh:
The boy tribute from District 11, Thresh, has the same dark skin as Rue, gut the resemblance stops there. He's one of the giants, probably six and half feet tall and built like an ox.http://jezebel.com/5896408/racist-hu...the-movie-made
This is RUE