High paying jobs tend to be in expensive areas, the daycare and baby shit probably bumps their expenses significantly too.
They don't mention what their house interest rates are, that alone could take out up to half of their income.
300 a month for gas sounds insane too. It's all down to their individual circumstances, self inflicted in other words. I suspect they got a nicer house than they could comfortably afford, in an area that is a bit too posh for their budget and too far from their workplace.
I think I hear the world's smallest violin playing.
