You're joking, right? How would that differ from allowing the Foundation to assume copyright of all entries? If you wrote the article of the century, pretty much by yourself, some how I doubt a byline of "From Wikipedia, by Wikipedia" wherever it's mirrored would be satisfactory to you. Not without at least a link to the edit history.
If that was the way the copyrights worked, if they choose Wikipedia as the medium to publish what they have written, then they chose to accept that as the byline. You don't submit what you don't expect others to rewrite, anyway.