The California State Board of Equalization (the taxation department) defines the word "Publisher" in the following manner.
"Publisher" means and includes any person who owns the rights to produce, market, and distribute printed literature and information.
This is probably standard legal definition of the word and so we now know why The Watchtower Corporation chose it to describe the activities of the Witnesses as they go door to door. It is not to preach, but rather to distribute literature!
The Witnesses's are nothing more than literature distributers and they didn't even know it!