I wouldn't mind having same-sex marriage in the game, but I think one of the reasons it isn't present (other than the fact that a lot of people are uncomfortable with it) is that we have a second generation of characters. I mean, I know that same-sex couples can use a donor or something but that sort of complicates things and doesn't really make sense in the Fire Emblem world (at least to me).
Why is yes in all caps? I think it's an issue, but I don't feel anywhere near that strongly about it. It's a minor thing to me, just like the models apparently not having feet is minor to me. It doesn't detract pretty much at all from the experience, but I'd still like the option.
Failure is unimportant. It takes courage to make a fool of yourself. -Charlie Chaplin