Fake Memoirs

What is with all of these memoirs that are turning out to be fake? How do people think they can get away with this in the Information Age? We all know about A Million Little Pieces, I think Oprah made sure of that. Then several of my book news sources wrote about a famous Holocaust memoir called Misha: A Memoire of the Holocaust Years, another best-selling book that took over a decade to get outed. Now this morning people are talking about Love and Consequences by Margaret B. Jones. She claimed in her memoir to grow up in a foster family, be half native-American, run drugs for a gang, and graduate from the University of Oregon. Yet in reality, she grew up in a very privileged, all-white family, graduated from an elite private high school, never went to the University of Oregon, and most importantly, never lived with foster parents or ran drugs. The most interesting part of this story was the book was only published a week ago and it was the author's older sister who outed her when she saw her picture in the New York Times. The publisher pulled all of the books and canceled all tours. I assume since these three books were best-sellers and critically-acclaimed that they are well-written. Why don't the authors just market them as fiction?