Gay marriage is a no-brainer

Gay soldier says career is almost certainly over 
"A GAY member of the Australian Defence Force who served as an army psychologist says his career is almost certainly over after he was subjected to a death threat and hate speech online by other soldiers, which he says were not investigated properly for a year."

What I don't understand is why any Australian who prefers people of the same gender would join the Australian Defense Force. Given the strong anti-gay sentiment on both sides of parliament at the moment, with both Labor and the Coalition rejecting equality for homosexuals by opposing gay marriage legislation.

Why?

There is NO good reason to oppose gay marriage. None. All, and I literally mean ALL opposition to gay marriage is based on bigotry and hate. There is no logical, scientific reason to oppose gay marriage.

I'm not going to go into a long rant disproving the arguments against gay marriage one-by-one. If you want that, you can read that sort of thing here and here.

What I want to know is why it has to be an issue? There is nothing stopping gay couples from having kids. A lesbian can quite easily get herself knocked up, and I would love to see someone try and argue the case that she shouldn’t be allowed to keep her child because the child deserves/needs a mother and a father. It's possible for gay men to have kids as well. A number of gay men don't even come out until after they're married, and possibly even have kids (my wife had a friend whose dad was gay). Would anyone argue that a gay father shouldn't be allowed to raise his kid (particularly if, say, the mother was dead or otherwise unable to raise the child)?

Gay couples can easily raise kids. So that's not an issue.

Infertile couples and couples who don't want to have kids are still allowed to be married. So procreation isn't an issue either.

Why can't marriage just be a recognised legal union between two (sufficiently unrelated) consenting adults? It's easy. It's simple. It harms no one. It still doesn't allow for polygamous marriage (which I'm not fundamentally opposed to, I just haven't yet worked out a consistent definition for it, so I shaln't mention it further). It doesn't allow for underage marriage (under 18's can't legally give consent, so really, by specifying consent, we don't even need to include adults in the definition). It doesn't allow for bestiality (animals can't give consent).

It allows marriage to be to you what you want it to be. It allows marriage to be about love, if you want it to. Allows marriage to be about religion, if you want it to. Allows it to be about whatever you want really.

Now, I'm not gay. Allowing or disallowing gay marriage does not affect me in the slightest. I just can't stand bigotry, hypocrisy, or logical inconsistency.