Wolf, I would hope and assume you don’t trust everyone with a yarmulka for kashrus.
Not necessary everyone — but I trust my mother. I trust my sister. I trust my Rav. I have friends that I trust.
To trust, literally, no one beyond one’s wife is, IMHO, an example of a chossid shoteh. When he makes a bar mitzvah or a wedding, is he going to ask his wife to cook everything?
The Wolf