I'm not even sure I would call it "low income households", more like "older building/houses". Plenty of expensive apartment units are in old buildings (I'm looking at you NYC) without proper ventilation.
I own a unit in a co-op in a building that is over 100 years old. I have a gas stove. There is a vent on my above-range microwave but it's just a filter that blows it back into the room. I do a lot of cooking. I'm in danger.
Hah. I just got my first one today. I immediately chalked it up to spam, but didn't know it was so widespread. Hilarious.