Well people tend to treat it like one. Life long commitment by two people to each other is not a scam. For me marriage is holy covenant between my wife and I before God. The fact that others do not value their word, their spouse and deep commitment says more about them and modern society than marriage.

I've also found people are looking for excuses to do things they know are wrong. Reasons why they can do what they want beyond just admitting that is the reason. Rationalizing behavior is real.