Helps preserve our natural resources. Cheap distribution over the Internet by downloading a file. No shipping and handling charges. Dozens can be carried in a reading device for travelers. A far greater diversity of books can finally be economically published.
Profit margins can be much greater while still delivering the value.
Permission settings can include print out and other functions. Make an ebook more secure from theft and sharing than a paper book. Ability to up-sell a printed version. Easy to update an ebook. Never out of print.