It can be very difficult to get a baby to sleep. You have to rock the baby on your shoulder for more than 20 minutes and gently sing a lullaby. When you finally get your infant child to sleep you don't want to hear the sound of a noisy car outside waking the baby up.
What people do is they remove the exhaust pipe on their car and put a bigger one on the car that has fewer mufflers, you can hear the cylinders in the car burning and sputtering because the sound is no longer being muffled. They also put very loud speakers in the car because everyone wants to hear their shitty music blasting out. Then they add a turbo charger but it doesn't fit engine area so they change the hood door so it has a dent to fit the turbo charger, so now the noisy cylinders have a more compressed fuel mix to make even more noise with. Finally they over rev the engine while they are waiting at the lights so every person can hear their cylinders sputtering and their noisy drum music playing.
Some people only think about themselves, they don't think about other people. They don't care that they are disturbing people's infants so they have to work harder to get their child to sleep again. or maybe someone is just watching something on TV and they don't want to hear their horrible noises. They don't care, they disturb everyone.