The less people know, the more sure they are that they are right. I've noticed that overwhelmingly the dissaproving comments that I get come from men who are sure that polyamory is some sort of cover for women to indulge their selfish desires and for treating their husband's badly. The fact that these women are overwhelmingly looking to date other poly men seems to be lost on them, as is the fact that many poly people aren't married in the first place.