This is what the Atlantic reports. The central reason for it is best summarized in this paragraph:
And like many Kindle owners, I’ve found that I buy more books than I used to. The impulse purchases are now completely irresistible: I can have the new memoir about someone’s dead tax cheat of a husband right this instant, rather than waiting two whole days . . . by which time, I’ll have forgotten about the Washingtonian excerpt that made me want to read it.