I think the problem, in the end, is making it pay. Bookstores that try to survive just on book sales tend to have to be small, cramped spaces with just enough room to walk crabwise between the shelves (I'm thinking specifically of White Dwarf Books). Of course, those of us who frequent those kind of places are perfectly willing to put up with that.
If you want to make a better go of it, though, you have to either have an attached restaurant, or have Bob's Book Store and Bait & Tackle Shop, or some other hook.
I've often wondered if a New/Used bookstore would work, where you could sell books back to the store when finished. Used books might be on sale for 50% of list, and you sell them back for 20% of list. Effectively, you're renting books.
I will say that a reading area (accessible only after you've purchased the book -- Chapters learned that the hard way) would go a long way to making a book store more attractive. With a coffee/snack bar a la Starbucks, you could probably make a buck.