I know this is weeks old by now, but can I just ask when you went? Actually, it doesn't matter. MK is so substantially busier than those other parks, keeping those restrooms clean only lasts so long. It does come down to managerial decisions on staffing the bathrooms sometimes, but most of the time the upper hub area has 5-6 restrooms to clean in rotation and town square has 3-4 (busier) restrooms. So one person may go around and clean a restroom and it will look great, but by the time they get back, it's a wreck and someone shat all over the floor.
Again, it does come down to managerial decisions on staffing, but those are normally made the night before based on park attendance predictions. So you do have a valid point and expectation that the restroom should be spotless, but the way things are run, it's almost impossible. And trust me, I wouldn't be saying this if I didn't have the first hand experience.