It could be a case of implicit vs explicit knowledge. In the context of evolved culture beliefs, the foophobia may serve some real purpose, even if most/all of

It could be a case of implicit vs explicit knowledge. In the context of evolved culture beliefs, the foophobia may serve some real purpose, even if most/all of the enculturated individuals can't explicitly state what the real purpose is. It could be that, like dietary restrictions to reduce the spread of disease, the foophobia is no longer needed, but keep Chesterton's fence in mind before you say it's unneeded.