I think there is such a thing as socio-economic cultural quarantining to protect your kids from bogans.

Nothing to do with race whatsoever.

It is likely my DD will go to a private school because most of the public secondary schools in this area are full of ferals.

Am I quarantining her from their influence? Absolutely.
I want to do that too, BUT I don't want DD1 to go to a cultural (and religiously [is that a word? lol]) homogeneous school. She needs to learn about the diversity in Australia and around the world. How to achieve that baffles me slightly ...