For me the marginal cost is the additional song, not the
additional copy of a song.
From the perspective of the musician, who sells to a record label, yes. From the perspective of a record label, and thus what determines the prices for customers, the marginal cost is zero. So the record labels need some other revenue stream, and hence the push to control the entire 'celebrity product.'
Yes, I get this point. I am just saying that there are other ways to look at this and that there still are plenty of costs in making music that generate plenty of profits.
Finally, we should be happy when marginal costs are 0, it means free for all, more for all. It is only who wants to go back to the State economy that can find flawed arguments against it.
