The parsimonious reason is that people write songs about comfort and large, happy families, not about AGIs and statistical households of 3.3 to 3.7 people with 1 to 1.44 breadwinners. Songs (and media) reflect cultural values, not cultural realities; see also rosy movies about the "good old days" of 1960s USA being not particularly representative of the period's racial and economic strife.

Because people dont accurately represent their situations? This seems so silly. West Virginia has a huge culture of music singing about how its a state of coal miners, when in reality, there are less than 15k working in the coal mines, with a population of 1.75 million.

That does not indicate that there are secretly a lot more coal miners, it just indicates that people are clinging to and showing off an identity that they like and want to be represented by.