"You are right that a CC licence is quite restrictive in some cases, preventing a map from being included as part of a larger work unless that work is also CC-licensed."
If a map printed in a book would be treated like a photograph printed in a book then I don't think this worry is true. See the discussion in the cc-community archives. Same for a newspaper article and what have you.
I don't like that this is true and keep trying to get BY-SA changed to close what I consider to be a loophole, but that hasn't happened yet.