What would have happened if The Sorting Hat had insisted on sorting Harry into Slytherin? Or what if Harry had become friends with Draco Malfoy instead of Ron during their first journey on the Hogwarts Express? Wander into alternative Harry Potter universes here.
She's going to be constantly teaching nonsense creatures like the Crumple-Horned Snorcack. It'd be hard to study creatures no books have been written about.
Hm.... it just seems like the kind of thing J.K.R would do. I would think nothing of it if every time Luna spoke, she talked about a different animal, I would forget about it. She's reinforcing it. She wants us to remember it.