Oh you're sure, are you? Have you ever talked to custodial CMs? I had one tell me that he tells his family NEVER to wear sandals or flip flops or sit on the ground (and touch it with their bare hands).
How often do you think the ride vehicles are steam cleaned or fully cleaned with cleaning products? The answer is "NEVER". This includes seat belts and lap bars, the bars or handles you use to get in or out, and the surface upon which you sit.
In all fairness, there are some things they do better. I know someone on the safety team in their department who took the blood-borne pathogens class and it was very clear and comprehensive. But a general recommendation is to use lots of hand sanitizer during your visit and avoid touching common surfaces like railings as much as possible.
