@Riot: Previously unused voice lines popping up in skins?

I was testing out the new PROJECT skins on the PBE and I noticed something rather peculiar about Fiora and Leona's skin in specific. On top of their fancy cyborg voice filters, they were saying new lines. One line each, mind you. Fiora's being "Let them eat swords." Leona's being "Pen or sword, the shield is mightiest," and "The day is upon us." Lines neither champion says in their other skins. Seems like it might've been an accident including them (filtering all of their voice files, probably automatically with some program, and not really paying much attention to what lines go through), though they sound really cool and fit the skins in particular.

This all brings up a couple of questions: Are there other champs with unused voice lines, either because they aren't good enough or just don't fit? And was the inclusion of these "new" lines in the skins an accident or on purpose because they fit the skins?