It's not about seeing marriage as "just a contract", but ensuring the rights of people. It goes the same for straight, non-married couples as well, that they do not get the same benefits as married couples do, because a legal marriage binds two people together to share property, assets, etc.
This would be the only reason I would ever get married, but personally, I am so saddened by the way so many marriages (including those of my parents and other members of my family) end. In the end if it doesn't work out (which, according to statistics, the majority of American marriages don't), you have a major, uphill legal battle to extricate yourself from this "contract". Nope, not for me. If I do find someone that in the end isn't going to work out, it is a lot easier to sit down, and split up things, versus involving so many third parties (lawyers, judges, counsellors, etc) it could make your head spin.
This is why I am against marriages, but I will admit there are some excellent advantages to having this legal contract, but I would only enter it if I was 100% sure that this person was the person for me, for life.
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