What "Going Solo" says about marriage

Among other things, Eric Klinenberg’s hot new book, Going Solo: The Extraordinary Rise and Surprising Appeal of Living Alone, calls attention to the continued free fall of marriage around the world. 

The corollary to Klinenberg telling us that the number of people living alone today is the highest it’s ever been (and that only 1 percent of married persons do so) is that marriage is in a nose dive. Government figures agree. Statistics collected by the Centers for Disease Control and Prevention show that the marriage rate has dropped every year but one since at least 1990 and in 2010, the most recent year yet reported, is at its lowest ever—6.8 persons per thousand—for the second year. 

Fewer U.S. couples tying the knot.

That being the case, the array of privileges accorded to married persons (higher incomes, richer employee benefits, and lots more) are being doled out to a shrinking population with no apparent means testing or accountability. Simply put, on what basis do married people deserve the goodies showered on them? 

Setting aside the bearing and raising of children, a compelling but entirely separate topic, what exactly do married couples contribute that, presumably, unmarried couples and single persons do not?  

I’m all ears.