It isn't about what's acceptable it's about what's the lowest common denominator for solving the problem, and piracy is clearly the answer to that equation. Ethics and morals are not universal, just because a person put time into it and they don't want to see their work devalued doesn't mean they are entitled to economic gain from it (an a-moral goal when they could simply release it for free)
I believe that information is free. When I finish writing my book I expect most people to pirate it. I will be honored by the ones who support my art; but there is no curtain up to hide what is going on, they are choosing to support it during a time when they could share it with each other. They are giving me value because they want to see more work like that produced, or they want to see behavior like that rewarded.
The economy is changing. If piracy is going to be this big of an issue for this long after napster, I can't wait to find out what people will think about 3-d printing piracy. Your same arguments won't hold up when the difference between pirating (information) and not pirating is being able to have tools available to you that do a lot more than just entertain you. The anti piracy laws will crumble as soon as someone 3-d prints a medical fix used by a large amount of the population, or delicious food, ect. Suddenly it isn't about entertainment and economy and value anymore; it's about human value and letting other humans live because information costs nothing, and it's totally immoral to hide that information and make them pay when it costs nothing.
I think anyone who is anti piracy needs to get with the program. Even without the pirate bay, we are talking about a decentralized animal naturally selected as governments try to kill it off, and like a hydra it pops up with more heads every time you kill an old version of it. Even without the internet, there would be piracy because it fills a natural role. Eventually it will be the most natural role, because as time goes on people will be forced to accept the idea that they don't own anything, it's just information being traded- and while information does have value, if that value is "infinite" what does that say about piracy?
To pirate, or not to pirate. That is the question.