I work in a commercial cabinet shop and with the exception of hardware that usually takes Pozi2 or Phillips2, everything else is done with Robertson2 or the combo ones that are "supposed to" be compatible with R2 and P2, but they don't do so well with P2.....which sucks to begin with.
We buy them in bulk, something like 30 or 40 pound boxes. They are not an off the shelf thing at the local big box retailers though. Torx is slowly taking over there for the DIY market. They are better for the average guy who now drives screws with power tools, but in the grand scheme of things, that's fairly recent.
For driving by hand, in a homeowner situation, phillips or slotted is still more common. I would bet that the average guy doesn't even own a dedicated hand driver for Torx screws. He would have to use an insert bit in a 1/4" driver handle, but you can bet on a a Phillips or two and a slotted driver too.