The worst case of unreasonable inflexibility I've ever come across was at the Willamsburg Inn in Colonial Williamsburg, VA. We have British friends that have lived in the States for many years and have joined us for Thanksgiving many times. The day after Thanksgiving we had diner at the Williamsburg Inn, nothing special to be honest.
Their daughter has many challenges, including being non-sighted. She wanted the chicken fingers from the childrens menu since it was the closest thing to finger food available. However, she was about 2 or 3 years older than the posted limit for ordering off of the children's menu and the Inn staff would not allow it.
Would never go back and heartily recommend anyone to stay away as often as I can.