It's funny how specific contexts give rise to "moral" problems. I mean, in order to ask the question, you must start from the premise that discourse is property, that property has an owner, and that someone will violate somebody else's ownership...presumably for profit..or possibly fame. But notice all the assumptions that have to be in place in order for the question to make sense: property, discourse as property, authorship, etc. None of these are absolutes or even real in many kinds of societies.
But I'll put it this way, if I create something of real value: a painting, book, poem...what have you, I had much rather it were disseminated to all corners of the globe (signed by as many people as want to sign it) than for me to have it as my property which I will only exchange for money or status.
Ideologically, the defense of copyright is equated to the defense of artists/creators, but in reality it is enforced on behalf of corporations and the rich. If there were 1,000,000 copies of Van Gogh's self-portrait, and it were not possible to determine which was the original, the rentier capitalist that paid millions for it would be out of luck, no?
Joanna