Let's say I have an imaginary friend named George. Are you OK with that? Of course.
Now, say we are out to lunch and I want George to have a seat at the table, that I talk to George with you present, and that I order a meal for George.
You'd think it's strange, but as long as my conservations with George are civil, you'd probably file that under "tolerance of eccentricity."
Now the check comes. You expect me to pay for both my meal and George's, but alas, I say, "George will pay for his own meal." Now it's impacting you, and you'd insist that I pay.
"But you ate some of the good off George's plate! Very rude, by the way."
What I'm doing isn't illegal until I try to leave the restaurant. You insist that I pay for George's bill, and I insist that he can pay for his own bill. You argue that I'm asking an imaginary friend to pay for imaginary money for real food. I insist my friend is very much real.
Now say I resolve this argument when George tells me he's a little strapped today. So I pay.
Now say I try to register George to vote. You'd say, "OK, now you've gone too far."
I insist you're discriminating against him and compare you to poll-tax supporters during the segregation age. Bigot.
I call you a bigot, who wants to take away George's civil rights, and insist there is no ontological difference between the imaginary and the "real." I can define people as I see fit -- who are you to say George isn't real?
You want to ban imaginary friends! We shall overcome ...
And you say, "I'm not against imaginary friends. I just don't think they should vote."
I ignore that and insist you're a horrible bigot who is just like those who opposed liberation for African-Americans. We shall overcome.
That's how strange pro-same-sex marriage arguments appear to me.
Same sex marriage is an ontological impossibility. We could not legally create one even if we tried. All we'd do is create an imaginary marriage and then swear it's bigotry to fail to acknowledge the impossibility.
And one step further -- you can't not know this. Natural reason and natural conscience tell you so. Just as in the above scenario, I can't not know that George cannot pay his own bill and that George cannot vote.
Same sex marriage is a mass delusion, as in, "extraordinary popular delusions and the madness of crowds."