G'day Steve,
And presumably for relevance. I can't see why we would be that specific about where someone lives. Some public figures may like to publicise their exact location, which would make it relevant, but most don't. The city they live in is plenty for encyclopaedicness, and their suburb is already getting a bit nosy...
AOL.
The suburb in which a politician lives can be very relevant indeed (at least in Australia; I don't know the situation in other countries). The suburb in which a film actor lives is not something we need to know. It depends on the specific circumstances of each person, but I'd say the vast majority of those living people we write about, a) don't need to have any more detail than city name included, and b) prefer it that way.
Cheers,