Do cars still need horns?

I understand that motor vehicles should have some sort of audible warning device. But do car horns still serve a purpose? 

1. When was the last time you used it?

2. Does hearing a car horn ever make you happy?

3. If it is meant to be a warning device, what are we warning about?

4. If it’s an emergency, you should have more important tasks than honking the horn.

5. Does using the horn make the situation better, or worse?

6. Maybe we need to bring back musical or programmable horns?

Like ringtones for your car.