Why don't parents work as a team more? It seems like you'd be more well-adjusted and sane if you covered for each other a night or two each week: if I still had time for the occasional pickup basketball game or bike ride, and my wife still had time for shopping with her mom or dinner with a friend. Surely one person could handle the baby for a few hours, right? Especially if the baby is in daycare most of the day anyways.
Or maybe people just dig the extreme sport of parenting, one-upping each other with stories of sacrifice and endurance.
This is the perspective of a childless person, so I reserve the right to change my opinion at a future date.