I remember being really disappointed after Nestle took over. When Kraft was the sponsor, many of the menu items at the restaurant were smothered with cheese. It was our go-to place for breakfast in the park, just to get those cheese omelets.
The original CoP was at the GE pavilion at the NY World's Fair, so no surprise that they carried over sponsorship for a while. I've always regretted that Disney didn't duplicate the multicolored, computer-controlled spiral lighting display that was on the shallow domed roof of the GE pavilion.
On the general subject of sponsorships, I was surprised to see that Disney still has sponsorships at
Disneyland, such as Honda for Autopia. Now clearly it's worth more because attendance at DL is higher than at EP, but I don't understand why Disney can't get and keep Epcot sponsorships at all. Consumer oriented companies haven't stopped advertising, so surely it's a legitimate opportunity. The only explanation I can conceive is that Disney wanted too much money for the number of eyeballs they were getting, or perhaps failed to deliver the number of eyeballs expected for previous contracts. MetLife appears to be a special case.
I don't remember whether sponsorships for specific rides still exist at MK.