The Greatest Mystery In the Known Universe

Why are there no McOnion Rings? McDonalds has market tested McRibs and Mc(cough) Salads. Even McFruit and McDog (local specialty).
Why is there no McOnion Ring to be had anywhere on the planet.
It's gotta be a conspiracy. A "no McRing" pact with the devil.
onion rings mcdonalds fried conspiracy devil