For a variety of reasons. The price drop on the WiFi only model made it very affordable, it's small enough to toss in my purse and read wherever I might have a few minutes that would be wasted otherwise. But most important was the battery life, I go tent camping a lot and can't always have a site in a developed campground (no electric), the nook will last for 8 - 10 days with airplane mode turned on. I love to read, especially on the beach, and the edge is just to big for that, plus I'd be a little afraid of getting sand in the ports.