Why do people advocate open source software; but posting text of a book is bad?
If people should write and distribute software for free, people should write and distribute books, magazines, television programming, etc, for free as well.
When you write opensource software, you are taking a work you created and explicitly deciding to release it to the public. It is your work, you are free to make the decision about how it is distributed.
When you write a work of text (or video, television, etc) and it is posted somewhere without your permission, they have robbed you of your ability to control distribution.
I think the opensource developers who take the position that all software must be opensource are in the minority; certainly many of them wish to maintain some form of control over their works, just like a book or television program publisher. If they had no interest in control of any kind, they would just release their works as public domain.
RE: I present to you a blatant violation of copyright