This is not exclusive to 2-income homes. A family very close to us makes do - barely - on a single, modest income. The mom stays home with their two young kids. Baby #3 is on the way. They wring their hands and fuss. Woe is us, we can't afford xyz. Woe is us, we have to decide between registering the car or buying food. They give me such dirty looks when I point out that the real choice is between buying food or buying cable service (with packages), buying high-speed internet, eating out several times a month, crawling the mall, buying the latest toys for the kids, keeping the thermostat at 70 in the summer and so on.
I know, but that's a budgeting problems (among other things) We're talking staying with your children.
However, those things you are describing drive me up the wall too!!!!