Also consider that many of us have to pay for child care when we go to our jobs. If I paid child care so I could get a second part-time job, I would spend more than I made, most likely. Not to mention, I would lose those hours with my children, not being able to attend their ball games, help with homework, or just spend time together.
And sometimes, you can cut every "want" out of the budget, and still, water heaters blow, cars break down, roofs leak, and any other multitude of things happen that completely wipe out that couple hundred dollars you had finally saved...