In the Netherlands, there is virtually no societal difference between people that are in a long-term relationship and live together, and married people. To the point that people call themselves husband and wife if they technically 'just' live together. My German girlfriend was shocked to learn this, in other countries (and cultures) marriage really is more of a 'thing'.
In BC, Canada, there is no practical legal difference between marriage and long term cohabitation. Not getting married and living together is rather normal, and comes with the same risk of financial segmentation and alimony or child support.
It's not because we are afraid of commitment, like this flimsy article suggests. We simply don't care about the symbolic ritual.