So if someone download the article dump and the image dump with plans of publishing it in the US (outside they would have to delete all the faur use images anyway, or obtain permission for each individual image) then your humorous fair use image from your userpage become a copyright violation for that reuser because without your userpage he has no fair use defence for it. This means that re-users would have to spend time and effort to purge these humor, parody and other orphanded userpage stuff from the dump, and while it's not rocket sience to automate such a purge it's still an extra burden on re-users that is completely unnessesary.
Wouldn't they purge the entire User: namespace anyway? We're not so interesting as for our user pages be republished in an actual encyclopedia.
