[cperciva]

It's best not to allow residential use in an industrial zone, because it tends to promote very low quality housing.

Presumably nobody wants to live in "low quality housing", and no developer wants to build housing which they can't sell; so this reads to me like a policy statement of "we'd rather that people are homeless".

Historically this has definitely been as thing -- American cities have prohibited low-income housing as a covert effort to enforce racial segregation, and in the early days of Victoria, Canada, free land grants were available to anyone who brought at least six servants with them -- but I'm not sure that such a policy has any place in modern society.

[wrycoder]

In that paragraph, I was only referring to industrial zones.