A Ferrari is not a terribly comfortable car to drive. Tuned well, it's got a hard suspension and you feel the road in order to drive it properly. It can be unforgiving if you make a mistake. It's got no room for the crap a mother or a father needs to haul around. Difficult to put a car seat in there.

Middle class cars don't look like a Ferrari because the Ferrari body and look enforces some decisions on the designers and the drivers of that car. No hauling around of crap for you. Even if you manage a child car seat, the kid will be screaming the entire time when it feels every hard bounce in the road. Your body is jarred as well. It's a sensitive car that requires an alert driver. Will you enjoy having that alertness day after day drive to work and back in congestion? Probably not... You want an easy driving car with a comfortable ride and room for crap. And voila you have a modern sedan.

Edit: voila and not viola. I've got orchestra on the brain.