It's a surprising finding, in part
because desktops aren't the most enjoyable nor convenient device for reading ebooks, and partly
because most ebook
publishers and retailers have prioritized
mobile, ereader and tablet reading experiences over the desktop.
Indeed, for all of the praise I just heaped on AMP with regards to monetization, AMP CPMs are still significantly lower than traditional
mobile web pages;
publishers, though, are eager to support the format
because a rush of traffic from Google more than makes up for it.