The times of the single income family are long since gone, and we now have to come to the reality, that it takes two incomes these days to make a living. If you disagree with this that's fine, but I'm sure you haven't lived on your own then. With that being said, it's no wonder families in todays world are splitting up. They have less family time together, increased stress, and a schedule that may not be all that sensible.
Years ago you had people working on their own farms, as a team, they depended on each other for survival, or the man of the house would work, but they didn't need much, because things were cheaper, people got by with less, did their own gardening, and canning, also there was not as much demand for things as the world was not so sophisticated.
Today people move on to form another family, because they think it's easier or they need a break. Then you end up with the Brady Bunch. Seldom do the new families agree on each others parenting methods, and favor their own, because they have more control, over them, and thus see their own as good, because they are the leader, and responsible for their party no matter what happens.