[Tempest1981]

Why can't the map serve multiple functions? I guess I wasn't overloaded by the detail.

[AJRF]

I would guess that placing labels on a map has some cost. Not doing this(especially over 3G, 4G, EDGE) might have some gain in loading time.

If you need that fine-grain detail zoom in?

Not saying I advocate this approach, but thought I would try give you an answer :)