American social and political culture has shifted rather abruptly towards support for same-sex marriage. Many opponents of same-sex marriage have shifted their rhetoric with it. They have changed focus from increasingly unpersuasive primary arguments (such as appeals to religious norms) to arguments that same sex marriage will have unintended consequences threatening the rights of others. They argue that legalizing same-sex marriage will have the effect of oppressing people who wish to exercise First Amendment rights to dissent from it, whether by speech or association.
Here's the problem: in doing so, some opponents of same sex marriage ("SSM" from here on out, because I am lazy) are promoting ignorance and confusion about basic rights by conflating government action, private action, suppression, and response speech. Ignorance — and I know I am going out on a limb here — is bad.