When the news of Amazon’s plan hit the web on Monday, a number of observers quickly noted that paying a monthly fee for access to a collection of books sounds a lot like something we already have — namely, a public library. So why wouldn’t people just go to the library instead of signing up with Amazon? The most obvious answer is: For the same reason millions of people have signed up for Netflix when they could just as easily have driven down to the local Blockbuster and rented a movie (an analogy that doesn’t bode well for libraries, since Blockbuster wound up going bankrupt).