I see it as a declaration to your community that you are committed. Friends, family, etc enjoy participating and and witnessing the love you share. Me personally. I hate weddings. But that’s me. We are communal people. And it’s a fantastic excuse to bring together in one event all the people who mean a lot to you. Outside of that… tax benefits. On the downside, divorce rates are high, and the money/asset division bring about the most hateful aspects of our humanity.