This is not the Gay Rights party.  People can have differing opinions without being homophobes, and your labelling them as such is very counterproductive.  But then, I've come to expect that from you.

I knew a man who explained his position on gay marriage thus:  Marriage is a hetero cultural institution.  Heteros have a right to preserve their culture just as gays, jews, blacks, women, communists, weedheads and sports-buffs do.

If gays want to have their own marriage this is fine, but they should give it a different name.  (Which is fine with me, as long as legally they are extended the same rights as heteros.)

Why can't gays, he posited, invent their own institution and have it adopted by the state?  Why must they insist on being allowed to infringe on a hetero cultural institution?

He had a point.  Heterosexuals invented a cultural institution which was adopted by the state.

Gays should do the same.

p.s.  Before you respond, consider that we have MANY exclusive institutions and legal rights extended to groups for various reasons, including race (indian casinos) sex (womens toilets, no men allowed) profession (unions, etc) and the like.