My reason? Economics. Allow me to explain.
You see, Williams-Sonoma sells a soup ladle for $39.95. (US dollars. You'll have to convert that to kiwimarks or whatever it is you use down there). Forty dollars for a curved bit of metal made to transport soup from one receptacle to another. Forty dollars!
No sane human being will buy themselves a ladle for $40. Not the foodiest foodie or the gourmandest gourmet. There is only one reason someone would buy a $40 ladle.
Weddings. Engaged couples will put a $40 ladle on their wedding registry, and guests will dutifully buy it as a gift.
Right now, the world economy is in a state of high-end ladle equilibrium, with supply of ridiculously expensive soup-moving implements perfectly meeting demand.
If we allow gay and lesbian couples to marry worldwide, it will inflate luxury ladle demand as same-sex couples register for gay-wedding gifts. The economic equilibrium will be thrown off as supply fails to meet the increased demand.
Soon, manufacturers will see a niche market in high-end souping items and enter the fray, vying for a small piece of the soup-transferance pie. Luxury ladles would flood the market, reducing their prices and prompting manufacturers to make even higher-end ladles to stay on t of the price point precipice. If left unregulated, this ladle rush could lead to a tipping point known as the Soup Event Horizon, beyond which industries find themselves incapable of producing anything other than ladles and raw materials used for the manufacture of ladles.
I don't have to tell you what happens next. Global economic, agricultural, and industrial collapse. The complete destruction of all human civilization and infrastructure. Soup kitchens will spooning out bullion broth with now-worthless diamond-encrusted ladles to the dwindling survivors of humanity.
All because gays and lesbians want to marry.
Just kidding - I'm cool with it. The basic human right of marriage should be open to all. Congratulations to you and your wife. :)