I hate to burst your bubble, but you'd better try to buy stock if you are going to degerm DisWorld. Think about all the handrails while you wait -- the safety buckles on rides, the sides of rides, the steering wheels, the controllers -- the strollers -- OH MY!!!
You have millions of people walking around without washing their hands in the bathroom, after they sneeze, pick their teeth, or scratch their noses and nether regions.

The money that changes hands, the items in gift shops that have been picked up by hundreds of other people, etc. The bathrooms are least of your worries!
Good luck!