I still do not understand why the cellular iPad exists.

We all hate the guy on the train standing there with the iPad in his face, just like the guy with the headphones. Having to balance that thing in your hands is stupid, and he's probably doing things that you could do on your phone anyway. What are you seriously doing that requires you to have a cellular iPad? A phone is so much more sensible on the go. I mean, I sort of understand why someone would have a cellular iPad Mini, but a full sized iPad? If you're taking it somewhere else, then chances are you have wifi there, and if you're going outdoors, you could just tether it with your phone. There simply is no need for the cellular feature, just like the camera on the back.