it is not the custom of even the religous jews in my vicinity to wear a kippah outside of the synagogue.
Perhaps your community believes that the halachos of the Shulchan Aruch are stringencies. Such as the halacha in Orach Chaim 2:6 not to walk four amos (6-8 feet) without any sort of head covering.
Personally, I define “religious Jews” as those who proscribe to the halacha. But perhaps that definition is a stringent definition.