The ceremony and the institution of marriage just isn't as important to people, especially the younger people as it use to be. It's not the gays fault, it's not anyone's fault. It's just the way it is today. Many people just don't care if they are married, and if they get married how they are married, or who marries them. Anyone can get ordained on the Internet and preform a marriage ceremony pretty much says a lot about how the institution of marriage is looked at nowadays.
It use to be a big deal. Now? Not so much. I think the whole concept of marriage has become minimized. I don't know if that is good or bad. I really don't care.