Picking up from the music posts last weekend. . . .
Country music draws from the world of adults: marriage, family, work, church, but also alcoholism, adultery, divorce. (Country music is not intrinsically more wholesome, though. It is very frank about sex–premarital, extramarital, but also marital–and is full of bad examples.)
The other popular musical genres–indeed, virtually all of pop culture, including television and the movies–draws from the world of young people: dating, singleness, play, undefined spirituality, drugs, premarital sex, romantic love, fantasy. (Notice that on television, virtually everyone even in ostensibly realistic dramas–NCIS, Law & Order, Bones, etc.–is single.)
It was not always this way. The blues draws on the adult world. Folk music. Jazz. Standards. The American Songbook. Classical music back when it was contemporary was made by adults for adults.