...and, apart from all of that, how the chuck would you ride a K without a helmet? Apart from very slowly. You'd either lose your eyelids, your eyeballs or your whole face, depending on the warp factor.
The guy in New York was piddling around on a Harley by all accounts so not exactly going ballistic. From the seat of a moving bike, the tarmac is even harder than it is if you fall off the kerb and that hurt enough the last time I did it.
Still, it sorts out the gene pool...