Syreeta Barlow at Word Riot has written a great essay about the weirdness surrounding the African American fiction sections of bookstores:

So what is it about the African-American section of a bookstore that seems so foreboding? You can find Jhumpa Lahiri, Paulo Coelho, Amy Tan, Khaled Hosseini, Gabriel Garcia Marquez, and other non-White but also non-Black authors in the regular fiction section in their alphabetized places. In fact, besides the African-American section, the only other fiction shelf that I see earmarked by ethnicity is the Spanish-language section (which also houses popular books like Twilight and Harry Potter en espanol).

Black authors such as Toni Morrison or Alice Walker will sneak into the regular fiction section, and specialized fiction by Octavia Butler and Walter Mosley end up sorted by their genres and not by the authors’ race. But this, too often, is the case only when an author has gathered a nice-sized following to expand past the limits of their skin color. Popularity, however, does not keep non-Black authors limited to a certain area of the bookstore.

Barlow writes about working at chain bookstores, where she was "instructed to specially designate Black authors to the African-American table, no matter how prominent they were, and to keep an eye on that section to watch for thieves." When I worked at Borders, they maintained an African American fiction section and a gay fiction section. I was not a fan of keeping them separate and told management so. But you can't just get rid of a section when you work at a chain bookstore; the books arrive preassigned to that section, and the entire store is laid out to sell advertising space to publishers, so if an employee tried to integrate sections, that employee would likely get fired.

Changing times also inspire different reasons to do away with the African American fiction section. One of the qualities that bookstores can claim over online competition is the capacity for a randomized browsing experience, and the opportunity for discovery that can only happen by accident. Amazon tends to only show browsers books they are likely to buy based on their history, which gets a little same-y after you buy from them over and over again. Bookstores need to open browsers up to new horizons that Amazon's algorithms cannot, and the more sections a bookstore has, the less opportunity for accidental discovery exists.