I also think many of us just have other platforms to read things like newspapers, magazines, email, web browsing etc (smartphones, laptops/netbooks/tablets, desktops, etc) that we really don't want or need the extra functionality. It is so much nicer and easier to pull up that type of stuff on my iphone or netbook that I would never consider using my Kindle for that. Just like I could never imagine reading a full lenght book on my laptop/iphone. The appeal to a lot of us is to use the Kindle as a dedicated ereader which is wifi is fine for many of us.
Plus, if you are like me, I tend to get distracted if I have too many features so I like to just read on my Kindle.