I would guess judging by the people I have encountered that there is a reasonably substantial number of people who buy ereaders as Christmas gifts for others who have never used one themselves.
Many will buy online, but for those who buy in store a slick integrated cover could be as big a selling point as other features.
When I was buying my PRS 350 the Sony store was the only store that actually had a working model. Future Shop, Staples and Walmart either had them behind locked cases in sealed boxes or non working models on display. Same last year with the Sony T2, the Kobo Glow and mini. And this is in Vancouver, a fairly big city. The Aura HD was on display working in a bookstore
when it came out at least. And the light did not really show off well in the store.
People who have a front light and love it will want the light. Others may go for the snazzy case that puts the reader to sleep instead.
Perhaps Sony is not as interested in ereader development as I would like, or perhaps they are taking a holding position while developing a leading edge product. (my fondest dream)
Still their company, their choice. If they chose to spend more time on other product lines, most likely they have sound reasoning behind this choice. I see no reason for all the wringing of hands and too bad they can't make anything nice anymore whinging. Sony is a lot more financially successful than I could ever hope to be.
Helen