Creative work has value; whenever I use, or take, or build upon the creative work of others, I am taking from them something of value. Whenever I take something of value from someone else, I should have their permission. The taking of something of value from someone else without permission is wrong. It is a form of piracy.
(This Randian [via PC] puts the point in terms of "the cardinal virtue of productiveness", but it shares the same propertarian core: "injustice would lie in denying creators the right to set their terms" for the values they create.)
[This] is the perspective that led a composers' rights organization, ASCAP, to sue the Girl Scouts for failing to pay for the songs that girls sang around Girl Scout campfires. There was “value” (the songs) so there must have been a “right” — even against the Girl Scouts.
More generally, propertarians are beset by the haunting fear that someone, somewhere, might enjoy a value without first obtaining permission from all who played a causal role in creating that value. This leads to intellectual property rights extremism, i.e. the view that creators should have absolute control over who else may benefit from their creations, and how.
To see just how ludicrous this position is, note that it makes singing in the shower a form of piracy, as you enjoy a value without paying the composer. Indeed, merely imagining the tune in your head could be an equally immoral rights-violation. These propertarian extremists (now quite obviously not any form of libertarian) are committed to accusing us of thought crimes!
The fear that someone might obtain "something for nothing" is not entirely new. Lessig describes how, when the camera was first invented, the reactionary propertarians of the time tried to restrict the value people could get from them. They argued that photographers should not be allowed to obtain free value by taking images of targets without permission. Thankfully, the courts rejected propertarian extremism back then, and instead ruled in favour of the "pirates". Thus we now enjoy photography without the burden of legal regulations that would effectively put this technology out of reach of ordinary citizens. Things could have turned out very differently.
Imagine how much emptier our lives would be if the propertarian extremists got their way, so that all values are privately "owned" and absolutely restricted by default. In the extreme case: you may never feel any happiness caused by another without first getting their permission. You may never think any valuable thoughts inspired by another without their permission. You may not creatively build on their work, or parody them, or create original "mash-ups" from unoriginal parts; not without permission. You may not conduct your private business using methods patented by your competitors -- and good luck getting their permission!
Of course, few propertarians would explicitly praise such a dystopia. But this is what their principles entail. If it's always wrong to get something for nothing, to freely enjoy a value without the creator's permission, then you mustn't hum your favourite tune. It's that simple. The principle is absurd. We should reject it.
That's not to say that there should be no intellectual property rights at all, of course. We need to create incentives for creators, and reward them appropriately. But we should recognize this pragmatic basis as the justification for our intellectual property system, and organize the latter accordingly. Once we get over the absurd and pernicious propertarian principle that creators have an absolute natural right over their creations, then we can instead start to look at the real, practical, issues.
We ought to arrange our institutions in whatever way would best promote creativity, reward innovation, and generally produce a flourishing culture. We should not simply assume that a propertarian "permission culture" is the answer here. In fact, we have ample reason to believe that it's not.
This should be especially clear to (real, Hayekian) libertarians. As Lessig puts it:
The charge I've been making about the regulation of culture is the same charge free marketers make about regulating markets. Everyone, of course, concedes that some regulation of markets is necessary — at a minimum, we need rules of property and contract, and courts to enforce both. Likewise, in this culture debate, everyone concedes that at least some framework of copyright is also required. But both perspectives vehemently insist that just because some regulation is good, it doesn't follow that more regulation is better. And both perspectives are constantly attuned to the ways in which regulation simply enables the powerful industries of today to protect themselves against the competitors of tomorrow...
Free market[s] and free culture depend upon vibrant competition. Yet the effect of the law today is to stifle just this kind of competition. The effect is to produce an overregulated culture, just as the effect of too much control in the market is to produce an overregulated market... A permission culture means a lawyer's culture — a culture in which the ability to create requires a call to your lawyer... The transaction costs buried within a permission culture are enough to bury a wide range of creativity. Someone needs to do a lot of justifying to justify that result.
See also: Applied Aesthetic Metaphysics.