If this "extension" costs more than $20, then it won't be worth it. Why not just pull the damn phone out of your pocket to do those functions you mentioned? Apple is trying to get into all kinds of niches, but the consumer will resist this one. How many normal people have use for more than 2-3 iDevices?
Like I said, it probably won't be for everyone. The iWatch will be as much a watch as the iPhone is a phone. Will it cost more than $20? Yes, probably. Will it be worth it? Evidently not to you, but it could to numerous others... just depends on what you value. It's quite evident wearable computing is the direction of the future (iPod Nano watches, Pebble products, Google Glasses, etc.)
People like you are good for society. To hold back technological innovation and the endless possibilities there of. It keeps us grounded and focussed on what's truly necessary. Luckily we thrive on a free market, so society will surely dictate if an iWatch is useful or not. People pay hundreds of dollars for a watch that only tells time... why is it so strange to think someone wouldn't pay half that for a device that does 1000x more?
If you can't understand the possibilities, features, and conveniences, then don't buy into it. Simple as that. No one's forcing you. Now if you held a respectable amount of stock in the company, then perhaps your concern would be more worthy and truly warranted.
Also, I have 4 iDevices and consider myself fairly normal. iPhone for texting, phone calls, pictures, internet browsing, etc. iPad for taking notes in lecture, having textbooks with me at all times, etc. iPod Nano as a watch, but also as a music device for running and working out. iPod for in my car (which has mainly gotten replaced by streaming Pandora via bluetooth from my iPhone, but meh).
A good analogy is the AppleTV. Why pay $100 to stream Netflix when you can just use your 360 or PS3 or hook your computer up to the TV? Why pay $100 to do anything that hooking up your computer to the TV will do just as well, if not better? I suppose it comes down to convenience, and people are clearly willing to pay for that. Why have bottled water when you can get water straight from your tap? Why have a car when you have two perfectly good legs? Why have a smartphone when you have a Point-&-shoot, a Ti-83, and a Garmin? Advancement in technologies that have withstood the test of time have all been related to convenience in one way or another. Most certainly people have refuted it, but that doesn't mean there isn't money in it.
