Is this an ethical question or a Hub page rule question? Isn't the whole point to get folks to read your hubs and other peoples hubs.
The most popular hub I've ever written which is the last one I published four days ago on the Illegal Criminalization of Marijuana the first comment was negative and voted down, which lead me to read four of this persons hubs.
Since then all of the comments have been positive and I've gotten over 1,300 readers in four days since I published it. Coincidence or just subject matter . . .
The point is that whether or not the comments are positive or negative as long as they lead us to read each others hubs, then they are serving a purpose.
I have found that most folks are way too serious for my taste and should lighten up, have a little fun with each other. Criticism is a good thing as I only learn from my mistakes not my victories.
As far as I'm concerned any one is free to link any one of my hubs to anything they deem worthy and feel free to provide scathing criticism, it is impossible to insult me . . . or give me some good feedback, but since I'm the greatest writer the World has never known I need very little!