One of the No. 1 rules of having a baby in a car seat is to buckle the baby in. Otherwise, it defeats the purpose.
Here is a perfect example of why this is necessary.

While at a Home Depot, an infant in a car seat -- not strapped in -- is on a cart that is tipping over. A store employee catches the baby before they can smash onto the concrete floor.

Give some mad props to the Home Depot hero. While he probably thought he was just going to help some people pick out paint colors that day, he ended up saving a life.