Yes, we actually cracked down on them 2 years ago from not making it clear that the content was from Wikipedia. They have since changed their ways and have it clearly stated in the "Overview" section and properly attributed the Wikipedia contributors involved in the book. We looked into how they could change the "Authors" section, but the online sellers' platforms they were using (such as Barnes and Noble) don't permit more than a few names, which makes listing all of the contributors impossible and we didn't want them to say that Wikipedia was the author because that erroneously makes people think that they books were sponsored or introduced by WMF or the contributors involved, neither of which is true.
Additionally, we do not believe that not listing the contributors under the "Author" section online is necessarily a violation of the license. However, not listing them in the book, where the content actually is reproduced, was and they have since corrected that to the best of my knowledge.