There is yet another issue, which I have never seen brought up. Unlike physical goods, with information you know practically nothing about what you're buying until you've non-refundably consumed it, almost by definition. The only possible exceptions are very large aggregates such as books. And most available information, by volume, is simply worthless.
Let's say that a dime were deducted from my bank account every time I read a HN article, and given to the author. I would feel that most of the money is spent unwisely. Not necessarily because almost everything is garbage (Sturgeon's Law applies!) but because I have not had the chance to evaluate it before purchasing, since doing so is effectively impossible.
This makes the common comparison of proposed Internet micropayments to costs such as my electric bill rather specious, since every KWatt/Hour which comes out of my breaker panel is worth the same to me, and I know exactly what to expect from it.
I refuse to participate in any scheme which rewards the worthless 90% of a Sturgeon's Law universe equally to the valuable 10%.