Last try on my site as it seems that you do not to get the point, this could well be because my English is not good enough for legal discussion...
Shure, it is not allowed to copy and distribute a paper map because of copyright law, but this is because I would copy the whole map not just
the facts. As I do actually not know if such a map _does_ display facts
only it would be also unsuitable for the production of OSM data.
In OSM analogy: Our rendered maps are subject to copyright law (no objection here), but our raw data is not!
This is the whole reason why we started the discussion about ODBL after all, because nobody could confirm that our data is in fact copyrightable.
I wonder about the original post in this thread, because at some point in the discussion it has been explained that the CC-Organisation did tell us exactly this when asked and that we should use CC0.
Think about the commercial map data providers (Teleatlas and Navteq). If there would be such a strong copyright regime on the data as you argue, they would not need to obfuscate it in such a strong way as they currently do.