On polyamory, just a couple of examples:
LGBTQ Polyamory Chicago
http://www.meetup.com/LGBT-Poly/
and
Is it Bigotry to Advocate Gay Marriage but Oppose Polyamory?
http://www.patheos.com/blogs/euangelion/2012/05/is-it-bigotry-to-advocate-gay-marriage-but-oppose-polyamory/
Trouble with the consent hypothesise is who draws the line? Let's take paedophilia as an example. In the UK we once had the Paedophile Information Exchange (PIE) it had some very prominent sympathisers if not supporters, particularly on the left (e.g., Harriet Harman - http://www.telegraph.co.uk/news/uknews/crime/jimmy-savile/9614516/Jimmy-Savile-Labour-faces-embarrassment-over-former-child-sex-claims.html). Moreover, the international age of consent is also somewhat of a movable feast e.g., Germany @ 14 compared to the UK @ 16. So might the plus sign appended to LGBT include advocacy for those adult Britons who have sex with a 14 year old? I am sure that there are states where bestiality is not illegal e.g., Alabama, Connecticut, Hawaii, Kentucky, Nevada, New Hampshire, New Jersey, New Mexico, North Carolina, Ohio, Texas, Vermont, West Virginia, Wyoming and the District of Columbia (http://www.examiner.com/article/states-where-bestiality-sex-with-animals-is-legal). Are those gentle people in California being victimised if they are to be prosecuted for shagging a dog, who is to be an advocate for them?