Does everyone believe in Marriage

I don’t. My boyfriend and I been together for almost 7 years and we have the best relationship I could ever ask for, but we just don’t see Marriage as a step we need to take in our relationship. Like the vows one would take, we do/would for each other. I guess what I’m trying to say or ask, why does it take a piece of paper or taking someone last name declare you married, as if your relationship just went to another level.