Jesus Phantom, this is simple stuff. Right now, today, this minute, no state allows Polygamy and all ban it. When that changes, or even when there is a momentum to discuss it, it will become ripe, and then we discuss it. It isn't relevant to today's discussion.
You scream hypocrite, but ignore the extremely obvious: you are arguing for Polygamy because you fail in arguing against SSM. You raise the hypocrisy card, even though it doesn't further your argument. Let's say everybody who is for SSM is ok with Polygamy...then what do you do? Bring up dogs like OiT?
Stick to the debate at hand instead of moving the goal posts and trying to fear monger.