Piracy is similar to printing money: What is the consequence of printing money? Even though printing of a lot of new money does not physically diminish the individual money bills, at one point inflation kicks in and reduces the value of money. Then the price goes up and the value of money goes down. In other words, inflation does not harm the individual dollar bill, but it harms the value of money.
Just like money is being devalued through excess money supply (inflation), widely available free copies of standards can diminish the price value of the standard. Because the incentive to buy a standard would drop if the standard was available for free everywhere.
Inflating money harms those that hold money. Inflating standards harms those that create or sell standards. Therefore piracy is not OK, even if it does not diminish the original standard document.
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