You're welcome, and for the record, I'm equally fascinated by your position - that a corporation can change the ethics of my actions merely by wishing it so. Like, is this limited to corporations, or can regular people wield this magic? You seem to think that money changing hands is a critical factor - why so? If a moral commandment can be attached to a purchase, why not to a gift, a meal, a story, a forum comment? That's why I keep going back to the hypothetical about "By reading this you promise to give me money" sort of license. Yes, it's absurd, but that's the point - your position leads to absurdities.
And lots of them! Could a restaurant declare, "By purchasing this sandwich, you promise not to give us a bad review on yelp"? If not, how is that different? Would that license apply if the sandwich was free? What if someone else bought it for me? If I make you a sandwich and stipulate that you must declare it to be delicious, and it isn't, is it more ethical for you to break my "license" or to lie?
I got more! What about DVD region restrictions? If I buy a movie in America and the license requires me to buy a second copy to watch in Asia, am I ethically obligated to do that too, even though that doesn't have even a fig leaf of moral justification beyond the manufacturer's profit motive? Is it unethical to skip the unskippable ads? For that matter, how does this license magically transfer itself from the rightsholder to the manufacturer, warehouse, retailer, and thence consumer? If I sell it used to my friend John, has he "agreed" to a contract with whoever originaly published the media through the magic of transitive association? What if I give it away for free, or throw it away and someone picks it out of my trash?
We're not done! Does this magic travel backwards in time? What license did I agree to when I inherited my Dad's old Beatles albums on vinyl? Bandcamp offers seven different licenses for music, is it one of those or a different one? Am I allowed to watch in in Asia, or is it region-restricted too? If not, how do you know?
We haven't even discussed immoral licenses. What if the license says, "By purchasing this you agree not to show it to any filthy stinking [ethnicity] people", can I ethically ignore that? What about those Taylor Swift albums that she doesn't own the rights to, can we pirate those? What about a trans person who wants to read Harry Potter, is it more ethical for them to purchase the books or to bootleg them? Can I download Abbie Hoffman's "Steal This Book"? OJ Simpson's autobiography? Henry Kissinger's?
Etc, etc. You get my point, I hope, which is that the seemingly simple "piracy is bad because it's unethical to ignore a shrinkwrap license" position is actually fraught with contradictions and argumentum ad absurdums. Whereas, the inversion - breaking the license is unethical because piracy is bad - is blissfully free of these problems. It allows exceptions, as in "OK, Henry Kissinger is fair game but you still have to pay for books not written by mass murderers" without compromising its central premise. The only downside is, it requires you to demonstrate that piracy is bad in itself, which requires a discussion of the different ways it can help and hurt different artists in different circumstances, rather than a tidy one-line proof that all pirates everywhere are bad, QED.
This is a long thread and post and sometimes with all the hypotheticals it's easy to be misunderstood, so to be sure that I am actually taking a stand (as opposed to just throwing rocks at yours) I'll close by trying to clearly summarize my position. Media piracy is certainly ethically dubious, but its ethical position is not changed by the shrinkwrap license(s) that are sometimes attached to it. If it's ethical to pirate a movie, it is still ethical to pirate the same movie with a sticker saying otherwise, and if it's unethical to pirate a movie with such a sticker, it's still unethical to pirate the same movie without that sticker. That the license claims it constitutes an "agreement" is simply false by any reasonable definition, as proven by the fact that people regularly purchase media who demonstrate their failure to agree with it by word and action. The only purpose such licenses serve is that some corporate lawyer somewhere decided it might help them win some hypothetical lawsuit; it is the ethical and legal equivalent of wearing a t-shit reading, "By reading this shirt, you agree not to rob me."