People who use their phones in any social situation, whether in a restaurant, or movie is annoying. It's like you're trying to subconsciously tell others you're popular and have lots of friends.
I don't use it while walking, but I surely use it when I don't have anything else to do(waiting for bus/cab, in a cab/bus...). I can keep it in my pocket, but I would rather listen to music, browse news, read articles, blogs, check facebook, twitter etc etc rather than sitting on a bus and waiting for my destination.
To each his own. For me, the choice between "sitting on a bus impatiently waiting for my destination" and "browsing on my phone" is a no brainer. FWIW, it doesn't have to be the internet. I have offline books and video clips on my phone as well.
But that's tangential. Your original post was about people bent in their gadgets. I was outlining why I am bent into my gadget. If you are into leaning into the window of the bus and watching traffic, birds, landscapes, roadkills or whatever, good for you. I would rather be looking at my phone.
Here I have a machine that grants two of my wishes, I use it very often, and using it is very compelling. I dont think its ridiculous to say that when you carry such a powerful and easy to use machine, you start to think of it as being part of yourself, and "why can't you keep it in your pocket" becomes as strange and unanswerable a question as "why can't you keep your hands in your pocket", or "why can't you keep your eyes closed".
You can argue this is an unhealthy trend in culture, and an unhealthy propensity for people who live in an increasingly technological world, but it's unfair - I think so - to judge/condemn/pity people who have the addiction.
I am of the persuasion that phone use during certain times (dinner for example) is to be looked down upon. I even go so far as to consider those with headphones on in the street as not existing in my world. They are ignored. It is great to hear the other side of the argument.
As a side note...I also love my phone and am eager for the day they are implanted in our bodies and seemingly telepathic communication becomes reality. I guess at that point this issue become moot.