Why McDonalds Shot Down Burger King's "McWhopper" Pitch

The McWhopper Sandwich Proposal?

Burger King is offering to team up with McDonalds for a pop-up store in Atlanta selling McWhoppers. But, McDonalds says NO!

On Wednesday morning, Burger King took out full page ads in both the New York Times and The Chicago Tribune to propose for one-day-only a truce with rival burger chain McDonalds in order to open a pop up store in Atlanta that would sell a new sandwich called "The McWhopper." The McWhopper would feature traits of both sandwiches, and the store itself will be manned from employees from both McDonalds and Burger King and would also be co-branded. But, why the sudden change of heart? The day of the proposed pop up would fall on September 21, which the United Nations have marked as the International Day of Peace, and all sale proceeds would go to the nonprofit Peace One Day. In an open letter on the newly established, Burger King writes to McDonald’s:
Peace One Day is a non-profit organization campaigning to make Peace Day September 21st an annual day of global unity. They have a powerful rallying call ‘who would you make peace with?’ which inspired us to lead by example and extend an olive branch of our own. We’d like to propose a one-off collaboration between Burger King and McDonald’s to create something special – something that gets the world talking about Peace Day.
This is a pretty brilliant move on Burger King's hand. Not only are they drumming up publicity for themselves and a charity, but they are going to make McDonald's look really silly if they don't take the bait. Burger King has also put together a video demonstrate exactly how a McWhopper would work. McDonald's CEO Steve Easterbrook replied on Facebook that while it was a "great idea" and "inspiration for a good cause," he shot down the idea of a McWhopper and offered a much more vague proposal. "We love the intention but think our two brands could do something bigger to make a difference," he said. "We commit to raise awareness worldwide, perhaps you'll join us in a meaningful global effort?"