The list available from Guest Services is not reliable or accurate. Some things are labeled "gluten friendly" and some "gluten free", but those labels don't seem to mean anything. For example, at Rivals Sports Bar the allegedly GF fries are fried in the same fryer as everything else. We had a pleasant waitress who worked really hard at taking care of our needs, but she was completely untrained about allergens. We were only able to get a bunless $12 cheeseburger. She took the initiative(she was awesome!) to talk to her manager to see if he would discount it since I couldn't eat anything it was supposed to come with. He said no. When we asked to talk to him he was very friendly and offered us all sorts of things, but there was nothing safe. When I asked him if the two bunless cheeseburgers looked like $24 worth of food, he said no and took half off of our bill, which we very much appreciated. Kauffman Stadium needs an updated and concise list. If you have Celiac, I would suggest you just eat before you get to the park.
I had hotdogs with GF buns they supplied (came prepackaged). Brought own snacks. Unable to get GF list from Guest Services. Ok experience.
The Market Place has brownies and buns available. Throughout the stadium there are various snacks and bun-less hotdogs - so BYOB (bring your own bun). Ketchup and BBQ sauce are GF, too.