The only reason Copyright exists is because some thinkers in the 17th century decided that a time-limited mechanism to reward the makers of new ideas would promote creation and exchange of ideas more than it would hinder it.
This is close to the truth but not entirely correct. The precursor to modern copyright were the licensing laws put into place with the invention of the printing press. Printing anything without a license was made into crime, and this license to print -the copyright- was given to a printer only after the work had been deemed to be non-blasphemous and non-seditious. In other words, the inception of copyright was a regime of censorship.
After the censorship regime was eliminated, the printers had become quite a powerful industry. They lobbied for the ability to continue charging money based on the printing rights they held. This is when the argument you spoke of comes into play. The printers argued that if copyrights are not granted, the production of art will slow down or cease because it will be too hard for creators to turn a profit.
Nonsense. Law is simply morality that's been codified. We believe killing people is wrong, so we make a law to reflect our shared morality. We have also decided that it's right that the people who create artworks deserve some reward for that work. The system to make that reward possible is copyright. Saying the system is not working properly, and that you want to change it, is a very different statement from saying that breaking copyright isn't about morality. This is, at its core, *completely* about morality...the question is only whether the law reflects your moral view (or, better, society's overall moral view).
You are 100% wrong in almost everything you just said. First, let me start out by pointing out that there are two classes of laws -moral/rights based laws and utilitarian/instrumental laws. Only the former is about morality. Laws in the latter class are not based in morality but are rather intended to achieve some particular goal. Copyright law, at least in the US, Canada, and the UK, (among others) is a utilitarian regime (France, for example, has a rights based system of copyright). This is why the US constitution limits the power of congress to create monopolies in works, requiring that such monopolies must be in service of the promotion of progress in science and the arts (that is the utilitarian aim of the law) and must be for a limited period of time (recognizing that granting a monopoly in intellectual products is or may be a necessary evil). In conclusion, you couldn't be more wrong in your opinion of copyright, which is a regime intended to promote progress in science and the arts. If it ever fails to achieve that, for example by preventing people's preferred enjoyment of intellectual products, then it has failed in its essential purpose and should be amended.
Your "private transaction" argument is also legally questionable. For physical things, (and in US law) if you buy something you have reasonable reason to believe is stolen you will also have committed a crime: Receiving Stolen Goods [jrank.org]. It's designed to allow the state to punish fences as well as the thieves themselves, but laws like this will be cited in any discussion of similar behavior online. If you have reasonable reason to conclude that the person you're dealing with is selling you an illegitimate copy of a game, you are not free from liability. Your liability is certainly less than the person selling the thing, but you're not completely innocent in the exchange.
Intellectual products are not physical things, and it is completely erroneous to use the analogy of physical property. Copyright was never even referred to as "property" until recent history, and this change in language was largely a rhetorical move by rights holders intended to shift the opinions of people like yourself. Turns out that this was a good strategy, judging by your overconfidence in your flawed views. Copyright is a system of rights that may or may not make the purchasing of infringing copies wrongful, but whether or not it does, and the extent to which it does, will be based on policy considerations concerning the goals of copyright, and not moral considerations about the wrong of "stealing" someone's "property". In Canada, for example, it is perfectly legal to accept a CD with infringing copies of music, even if you know them to be infringing. What is prohibited is the reproduction of the songs, not the accepting of them.