Literary "hoaxes"

Anyone want to tell me why the writing of these two can't be just judged on its merit? I just finished a Million Little Pieces, and sure, I questioned the "truth" of certain things, but that didn't stop me from enjoying the work as a story, whether based on fact or otherwise.

http://news.yahoo.com/s/afp/20060110/ts_alt_afp/afpentertainmentus_060110183129