A content farm is a term slapped on a publishing site which puts out shallow and poorly constructed items. Crap writing, to be blunt, surrounded by Ads for which Google will pay per click.
Hence, paying to put ads around a piece of Crap which fools a search engine, like Google, into thinking it is a real article, and it appears in a Search, annoys them no end.
If Hubpages has crap articles and removes them, so that what is left is the good stuff, then there will be no reason to discriminate. If there's crap then what will happen is that when one enters a search term anything from a Content Farm site will be way at the bottom.
If Hubpages gets that blemish, that means if you wrote about George Washington and there are 1.4M entries for George Washingston, you will be LAST.