I work with people who live in suburbs that are located far from the city (as opposed to just outside the city limits). I've noticed that when they talk about people "living downtown", they don't mean people who live within the limits of this map, but *anywhere* in the city.
For instance, I was talking to someone, and they said they have a friend who lives "downtown." I assumed the person lived near The Loop (south of the river) or north of the river, but no further than Division Street. "No," they said, "they live in Wrigleyville." That's over 30 blocks north of Madison and State, which is where the address numbers start for north/south and east/west. That's not downtown. But I guess for people living way outside the city, anything that's not considered a suburb is downtown (though now that I think about it, there was one person who considered Oak Park, a suburb immediately west of the city, as "downtown").
So when I tell them that I live "downtown" I have to explain that I don't just live within the city limits. They often say, "Wow, you really *do* live downtown" (though I don't live in The Loop).