The practical benefits are pretty big, at the very least in the US. Not being married actually is a major detriment to families financial stability and health.

This is not to say you shouldn't marry who you love, but it is absolutely about practicality, stability, and settling down a core for the rest of your life. That may seem transactional, but that's what happens when you take a covenant between God and Man and screw over people if they don't have this agreement with another person.

Marrying my wife was an unbelievably large boon to our lives, and we filled out a bunch of gaps in our life right there. Before, we were living on the edge for years while I provided and went to school full-time. We plan on having the actual ceremony later on, when we do want to have a costly celebration of our lives. Otherwise, it IS just a piece of paper, much like a college degree.