Joyce Carol Oates made a marketing decision when she wrote the novel. Using Marilyn as the focus was an attention-getter. It was also a lazy decision. By using Marilyn, she knew her audience was immediately going to be on her protagonist’s side, but she didn’t want to bother with all the research and analysis that an actual biography demands. Marilyn’s dead. Why bother? You can’t libel the dead. It’s not right, but it is profitable.