I think in part this is a result of ever-increasing government. Hell, it's probably by design. When half of everything you make goes to some level of government, what can you do but work two jobs, or work a lot of overtime if you can get it? Obamacare virtually forces millions to work two or more part-time jobs to make ends meet. Leaves little time for much else.
I have no doubt "it-takes-a-village-to-raise-a-child" progressives are only too happy to have it this way. The less influence you have over your own child, the better they like it.