Actually, this isn't news to the thousands of authors who started _out_ being published electronically. Few if any of the successful epublishers--Hard Shell Word Factory, Awe-Struck eBooks, DiskUS--bother with encryption for the simple reason it's a waste of time and money.
But, you argue, that's not the same as Stephen King or Patricia Cornwell or [insert huge money-making author's name here]. No, it's not. But behaving as if every reader is a potential thief isn't exactly good customer relations. It's rather like a department story insisting on having every departing customer undergo a body search.