How so? In the early years of both DL and MK, Pepsi and Coke were both corporate sponsors and were served simultaneously in each park. Pepsi sponsored facilities and was served on the west side of the parks, while Coke sponsored facilities and was served on the east side.
Even though the sponsorship of the Country Bear Jamboree is long gone, Pepsi's influence has been forever immortalized in Henry's exclamation at the top of the show that the bears "have a lot to give," which was a reference to the "You've got a lot to give, Pepsi's got a lot to give" slogan of that era.
It was a harmonious relationship that was renegotiated when the contracts expired. There's no reason to think that Disney wouldn't consider renegotiating its current contract when it expires too, if they saw a benefit to switching to a different provider. Sponsorships and corporate partnerships come and go all the time. How would this one be any different?