This last trip we were really bummed out that they don't sell a Coronado Springs coffee mug. We found an old one on eBay but the design is really boring...
After resort hopping a lot, we found it interesting which resorts had special coffee mugs for sale and which didn't. Contemporary did but neither Port Orleans had one. Polynesian had a really dumb-looking one but neither the Yacht nor Beach club carried their own mugs. Animal Kingdom Lodge, shockingly, had no custom mug but Wilderness Lodge had two.
At a minimum, every resort should have their own T-shirt, mug, and hat pin.