Because the activist pushing this do not want equality. I know two gay couples M/M & F/F. Both couples reflect a quiet majority of gays not busy protesting. What most of the quiet majority wanted was to marry the person of their choice, share benefits and not get the crap beaten out of them regularly. They have achieved this goal and are content and there are few people who have a major problem with those 3 goals. The activists however must ensure the "Revolution continues" Without the constant push, they lose their purpose and possibly their paycheque.