Disclaimer: the post reflects my thoughts on the newly "surprise!" polys who seek to suddenly alter their relationship.
Thank you for posting this topic, as I've often thought the same.
I think there are people that are honestly surprised to find themselves loving multiple people at once. I don't see why that gives them the right to unilaterally re-design the entire relationship for their benefit.
I've often thought the "married and now poly" bomb was like going into work and having your boss suddenly announce that your job has been transferred to another country. "You can either move or lose your job. Decide now." rather than having any say-so in the matter.