I'm a great believer in a bit of muck, there are far too many anti-bacterial sprays and cleaners about these days, they are not good for us or the enviroment.
When we kept our pony at livery my daughter and I would spend most of the summer holidays there, and most days would not be able to wash out hand before eating our sandwiches as the toilets were vile, this was in the days before the hand cleaner gels we did have baby wipes but didn't always use them, we never had an upset stomach in all the time we did that.