Very true about computers. I find even with CDs I don't get the same thing as with vinyl though. It's just not as compelling an artistic medium.
As to putting it on a website, that could work and some people have done exactly that, but this is cool because it turns that novelty into a product you can sell (access to a restricted area of a band's website on the promise it'll be there in a year's time is a hard sell by comparison) and this is where people know to go to buy music now so the expectation that it will cost something is already in their minds. So this just works better as a saleable product.
As to putting it on a website, that could work and some people have done exactly that, but this is cool because it turns that novelty into a product you can sell (access to a restricted area of a band's website on the promise it'll be there in a year's time is a hard sell by comparison) and this is where people know to go to buy music now so the expectation that it will cost something is already in their minds. So this just works better as a saleable product.