Really? How about ritual sacrifice? Or legal execution? Or war? Revenge killings were pretty normal in early Germanic cultures, including England.
Or if you want to think about stealing, how about eminent domain? The appropriation of Jewish property by the Nazis? The confiscation of treasure trove by the British crown?
Lying: meet the legal profession.
There are many things we think are not okay which are, in fact, endorsed by our societies - at least, as long as it's the wealthy and powerful doing them.
Translation: "I don't understand a lot of what these people say, but I am reluctant to believe that there could be anything missing in my own education or intelligence, therefore I will ridicule the authors instead."
Many of the works we consider "great", and part of our cultural heritage, were produced before copyright, and many were also produced without the prospect of payment in the artist's lifetime. Even those who made a living through their work generally earned no more than a modest salary. The "impoverished artist" is a cliche, but it was the norm for a very long time. And yet, these painters, authors, and musicians produced their work because they had talent and drive, and a love of their chosen medium. Now, if you can't be bothered to write a novel because you won't get megabucks for it, then clearly you neither love writing, nor do you feel any particular drive to do it. So why should I care if you never write your novel?
And, by the way, books were being pirated centuries ago - and probably before that, too. Dublin was a big centre of pirated books in the eighteenth century, for example - and yet somehow the book industry has survived that, as well as the Xerox machine, the scanner, the library, and the good old "here, I've finished this - you have it". This is not a new "problem" - whereas the culture of making obscene incomes from little or no real work is becoming the defining problem of the modern world.
The bogosity meter just pegged.