People who don't wash their hands.
Think about it this way.
Lets say you walk out of the bathroom without washing your hands and then a few hours later forget all about NOT washing your hands and then you go to eat something. When you decided not to take the extra minute or two to wash your hands you also decided to eat all those germs that are in the bathroom.
Whats even worse.
Not only bathrooms have germs, any public area does. Places like fast food joints, grocery stores, department stores and more all have germs on everything that everyone else touches. You don’t need to wash your hands everytime you touch something but when you're going to eat or even prepare food for people you should always thoroughly wash your hands.