Good point. That always bugged me too about the term "gay marriage". It obviously rolls off the tongue easier than "same-sex marriage", but the slight convenience is not worth the inappropriate-ness of the term. Also, I think many people use it because they see bisexuals as being half-gay and half-straight, so "gay marriage" works with that incomplete meaning in mind, as it is a marriage for that particular "half". To me, it doesn't work for bisexuals because "Gay" means exclusively same-sex attracted. You can't be half exclusively same-sex attracted and half exclusively opposite-sex attracted at the same time. Ah, the Bi erasure sometimes feels like a very stale and rough eraser that sands away the paper...