Why the addition of Dr Pepper to the U.K. McDonald's fizzy drinks menu has not happened yet, I do not know!

The Coca Cola company and McDonald's UK have a deal where McDonald's can only serve fizzy drinks brewed by the Coca Cola company.

These drinks are: 

Coca Cola
Diet Coke
Coke Zero
Fanta
Sprite / Sprite Zero

What I do not understand is that Dr Pepper is owned by the Coca Cola company, in addition it is also brewed in the U.K. Therefore McDonald's U.K. would have no problem into introducing the drink to the U.K. drinks menu. In the U.K. Dr Pepper places above Sprite Zero on the "Best Sellers" of fizzy drinks on Amazon.co.uk. Therefore I believe that the addition of Dr Pepper to the U.K. McDonald's menu would be welcomed by consumers as well as McDonald's U.K. & Coca Cola U.K.

Please could everyone who loves this drink get behind the petition because I know you would want this as much as I do. Why this hasn't happened yet is beyond me as I know how popular and beneficial this could be for both company's and consumers.