There are many things which Luna is still trying to catch up with in the modern world, and entertainment is high on that list. She appreciates some of the current musicians, enjoys a few books, and sees the potential in cinema. But when she doesn't enjoy being at a play, she's going to say something about it.
And when a Princess talks, a lot of ponies listen.
(Part of the Triptych Continuum, which has its own TVTropes page and FIMFiction group: new members and trope edits welcome. This story takes place shortly after the events of Good For Nearly All Princess Labor, Public And Private, but no knowledge of that story is required for this one.)