If your kids have friends, you'll probably find yourself driving around as many kids as that fairly often. I was raised in a family of five and my parents had a minivan because nothing smaller would have been practical. Even if you can technically squeeze 3 kids into the back of a sedan, good luck going more than 30 minutes away without fights breaking out. And even if your kids are particularly well mannered, they still won't be comfortable. If you're driving a few hours to visit family, do you want to have a headache from fighting kids when you get there? Or kids in sour moods because their sibling wouldn't stop elbowing them?