Most people can live with 1 income, they choose not too. I know there are exceptions to this like Bucks situation. For the average couple you dont need the 250K house, the two car payments, boat payment, 4 wheeler payments or any of the other payments you have. This is a situation that people get themselves into that forces them to need the two incomes. I have been there!
I am in a good situation, I make enough to live in a nice home, and we live well. I took me long time to realize toys are not important. My family is more important than a fast car, boat, or any other "stuff" I think I need.
To those that "need" two incomes. It is not impossible to get to the point that you only need 1 income. you just have to work at it. We had two incomes in our home at one time. We were making enough money that I was spending too much. It seemed like every month I looked at the books and I spent 10k on something, but I was not sure what it was for.