NYC is no tougher or thick-skinned than any other megalopolis city out there. Having been through a few times I find that, if anything, NYC drivers are a bunch of whiners. As are drivers in other cities, in all fairness. Hitting a vehicle with which you disagree - especially one which will, in all likelihood, most likely either not hear it or not care - is for premium rush fanboys.

As a matter of disclosure, I have knuckle-rapped a couple of passenger vehicles which were closing in on me as if oblivious to my presence.