We measure things to escape from our perceptions. In the world of physics, we may measured the rates at which objects fall in order to escape the perception that heavier objects fall faster. In the world of economics, we attach a price tag to things to measure how much a product is worth. Now I'm not saying that we always choose to measure things the right way. You could choose to measure the rate at which a feather falls and compare it to a lead cannon ball, only to end up with a totally erroneous conclusion. Similarly a price tag may lead us to the wrong conclusion because of conflating variables.

The thing is, if you replace that feather with a lead bead that has the mass of a feather you will get the correct result. Air resistance is no longer leading us astray. Yet it was reductionism, not holistic views, that led us to that conclusion. We had to take a smaller piece of physics to understand how a bigger piece of physics worked and we learned about new processes while doing so. The economic value of copywritten works probably works the same way: if we reduced everything to the same price ($0, $1, $5, or whatever) it is unlikely that we would ever gain an understanding of the value of a given work. In other words, the holistic view tells us bugger all. Taking a reductionist view, by removing conflating variables such as advertising or an author's reputation yet retaining supply side economics (through copyright) would probably tell us more about the value of a particular work.