The Hobbit: The Desolation of Smaug opens with director Peter Jackson appearing in costume in the city of Bree. Staring directly into the camera, he takes a loud chomp off of a carrot (bookending a similar seen from The Lord of the Rings: The Fellowship of the Ring), and marches off. While this seems on its surface to be a tongue-in-cheek homage to Alfred Hitchcock, his manner and presentation takes on a meta-textual feel as if declaring "This is MY house". The rest of the film seems to cement this assertion.
Nevertheless, her inclusion does add some added context for Legolas' behavior in the LOTR film trilogy but, again, it isn't a necessary addition to begin with.