On the off chance you're just uneducated and not a nasty little bigot playing dumb, the marriage right carries a ton of stuff besides a ring and a ceremony and any moral satisfaction the couple may get.
The right to see your spouse in the hospital, even (and particularly) if their family doesn't accept that their child is homosexual and attempts to ban a partner. (And this isn't a hypothetical; if you google you'll find just heart wrenching stories.)
It eases medical decisions when a gay spouse is badly injured or dying.
If there are children, both parents can have the right to care for them and make decisions for them.
The right not to testify against your spouse in some legal proceedings.
The right to get joint medical insurance.
Retirement benefits, which are particularly important when a higher income spouse passes first.
edit: and a very important benefit: being treated as a first class citizen, ie one with the right to have your relationship recognized just like straight people have their relationships recognized.
The right to see your spouse in the hospital, even (and particularly) if their family doesn't accept that their child is homosexual and attempts to ban a partner. (And this isn't a hypothetical; if you google you'll find just heart wrenching stories.)
It eases medical decisions when a gay spouse is badly injured or dying.
If there are children, both parents can have the right to care for them and make decisions for them.
The right not to testify against your spouse in some legal proceedings.
The right to get joint medical insurance.
Retirement benefits, which are particularly important when a higher income spouse passes first.
And more. See eg http://www.freedomtomarry.org/
edit: and a very important benefit: being treated as a first class citizen, ie one with the right to have your relationship recognized just like straight people have their relationships recognized.