While I was at that Margo Lanagan talk, I learned that Tender Morsels was published as an adult book in Australia. There will be a YA edition down under, but it isn't out yet. There are also adult and YA editions of the book in England.
England also did an adult and kid version of the Harry Potter books.
I think adult readers would be very interested in Tender Morsels. I think they'd be interested in Octavian Nothing, too. Same with The Book Thief. Fortunately, we live in a free country here in the U.S. of A., so they can read them if they want to.
But they'll never want to if they don't know about them. Sure these books are famous in kidlit circles. But most adult readers are not part of our circle. They have to know these books exist. I hate to say it, but they need to be marketed to.
I know I'm a lone voice on the subject of adults and picture books and will probably remain so. But, come on! They market YA to adults in other countries. I'm not suggesting something revolutionary.
Or do we Americans figure adults over here bought Harry Potter and Twilight without anyone having to make a special effort so we just aren't going to?