I've seen a friend ask vague questions trying to determine what kind of population lived in an apartment complex she was interested in renting from, and quickly

I've seen a friend ask vague questions trying to determine what kind of population lived in an apartment complex she was interested in renting from, and quickly get blanket responses not wanting to answer such questions, with references to the Fair Housing Act. I don't recall all of the exact details, but, to your general question, I think the answer is at least "yeah, sometimes".