An Odd Abundance of Purple, or: Magentastic!!

Despite what Riot leads us to believe with LoL's gilded, golden emblem, there's a strange amount of champions who, in the splash art especially, seem to dedicate their respective existences to the perpetuation of purple. Including female yordles, there are around 20 champs that feature purple as the primary hue in their splash art. (And more, like Ashe, use a debatable shade.) This number is a relatively huge amount, especially considering the fact that many of the champions who have purple splash art/icons are not actually purple ingame. If any Rioter reads this, as I expect they will, please answer this: Why so much purple?