Still, it's not entirely the fault of publishing houses and book selling. Some weeks ago a friend who teaches English Literature at a one of the new universities told me (despairing) that her department had decided to take To The Lighthouse off the syllabus for 3rd year undergraduates because it was too difficult.
Never mind what you think about Ms. Woolf's work, To The Lighthouse, or what this tells us about the educational standards in the UK, how can people teaching English at university (or school for that matter) deem any book too difficult to be read? What are they there for? What is a course in English Literature intended to be?
There will be English graduates who have not read certain books because they are too difficult, and literature teachers who think they have done their job. And supply and demand being what it is, now there is a publisher who will provide for them.