Several parkways in the NYC area employ them.
Of course, said parkways don't have overhead lighting, so the idea there is that they're reflective and make the lane lines easier to see in the dark with headlights being the sole source of illumination.
Nobody know them as anything, though. I mention "Bott's dots" in casual conversation and I get strange looks. I then explain and get "oh, is that was those things are called?" and/or "why do you know that?"
Actually, I get "why do you know that?" about a lot of things. Comes with being a nerd.