why not? There are plenty on the wiki page and they are quite hard to import for the user. Why not ship them witch codeblocks?
Because the license for these is not clear. The wiki page has been delete once because the first contributor didn't like something (don't remember what now).
And more importantly they are not full. Someone has to go through all languages and make the theme work for them.
I see no one doing the work, so the themes are not included.
I have a plan to add support for importing notepad++, geany, codelite, eclipse and so on themes to cb_share_config, but this is very low priority at the moment.
If someone is willing to do the work, I'll be happy to review it...