There's the majority of people who are content with doing their own thing, and conforming to whatever it is they prefer to conform.
But there's a small vocal minority which are not only deeply concerned with being, and being seen as, "normal", but who seek to impose this on others, on everyone else. They would make it illegal to be "not normal", if they could ; or, failing that, pathological, which is where we are at on the subject of "hoarding".
In other words, people who like to impose their aesthetic preferences and their "norms" on others.
Perhaps experts / authors themselves are such ; and even if not, they are not far off, as effectively they have been the priests and enforcers of the "normal" via their discourse and models.
See also:
* Compulsive Diagnosing ( same, but with credentials, but sometimes even without credentials )