They might be focusing on being a pit stop v a destination, catering to in app views and being shared mostly via Twitter and all that
What's interesting about the Flipkart example is that they have a fully-functional website available which they serve to desktop browsers, but the website is blocked to mobile browsers. Clearly they have decided that they prefer their mobile users to use their app, not a website.
One of their acquired companies Myntra is now app only. Only have a pc and the internet ? Sorry. You can only purchase from our apps.
Myntra sales drastically dropped after going app only. http://goo.gl/JQy6IX
I don't think expecting a new audience just because you have an app is reasonable. I'd be interested in seeing how many new users they generate with just the mobile web site - I suspect that ultra loyal existing readers may take the time to bookmark their site and come back, but would be very surprised if their overall usage doesn't decline.