Which is a nice hypothetical. Fact is we really don't have access to their pdf sales research. All I can do is draw on my own experiences, both with people I know in real life and with what I've read on the forums. A lot of people seem to want pdfs, for the right price. A lot of people also seem to want both pdfs and physical copies, and some of the people who've said they want this have said they'd want the pdfs in addition to more than one physical copy of the books.Or maybe their market research has shown that PDFs aren't heavily desired. They do have digital offerings available for sale of all the books, with more added value than a PDF.