Agreed, the whole ebook wars missed the point that for fiction books only 10% of the cost of producing a book is the actual printing press, another 10% might be distribution (but given most publishers had to hire new job positions for digital distribution, this didn't really go away it just got a name change).

Textbook printing amounts for between 10% and 30% (depending on things like glossy paper, number/size of pictures, etc). However, given that many textbooks come with a CD and often hours of video, it could actually be a very expensive digital distribution. It's very different serving a 1MB file to 10,000 people than serving a 700+MB file to 10,000 people. One of my wife's courses came with 4 discs for administrative assistant course, her college alone had 500 students starting each semester, which means you're looking above 2gig for a textbook per student. So over 1TB per college.

Granted you can easily buy that sort of bandwidth, but it's that they might have to buy 1PB of bandwidth for the sum total of a two-week period when school starts.

I think publishers would likely rather keep their deal with Fedex for bulk distribution than figure out digital distribution when there's no considerable cost difference in distribution and people are forced to pay.