It's cultural. In India and other places in Asia, honking is just to say "hey, I'm here, did you see me?" and prevent an accident, but it happens so frequently that sitting in traffic is a cacaphony of honking at all times. In (my part of) the US, honking is to express displeasure at whatever it is the other driver did, and is infrequent. In other places, they might as well not install a horn, because it never gets used.
It's used much the same in NYC and some other than areas. A quick tap to say "hey I'm here and I'm doing something" like changing lanes or pulling out of traffic
Aside: I really wish cars had two different horns. A nice little boop horn, to say "hey I'm here" or "lights green buddy" and then the big honking thing that says "you nearly hit me by rolling through that stop sign, pay better attention"
If you want to expand your mind, travel to south east Asia or India for a bit and see a different way of how billions of people live and drive every day.
I've done it. I've got a little loud speaker that plays a soft awooga sound when I press a button, but it would be nice to have a factory option, or even a standard