It's not just used here in Canada, it's used everywhere. If you go into any of the big box stores, and go to the hardware isle with all the screws... 90% will be robertson. Anything residential electrical... Robertson. Basically any screw used in residential construction.... Robertson. The only thing I can think of that we regularly see phillips screws in is when they come with something that you have to assemble. Hate them! Granted, when they come with diy-assembly stuff, the quality of the screws are mostly cheap junk to begin with, but ermergerd do they strip easily.
Oh... drywall screws. For some reason drywall screws are phillips. That's the only "building supply" screw that I can think of that isn't robertson here.
It's hip to be square.

saw this earlier via another site and I agree some how to videos are hard on the eyes

I've used this technique very effectively to outrun confused park rangers as well.

I've used this technique very effectively to outrun confused park rangers as well.

Are you sure it's removable? The quick looking I did suggests it's embedded/symbolic of the potential, not actually usable (which would be very complicated)

Sweet are the uses of adversity.

That was fun!

Deliver the goods.

I can relate. I shot Expert with the M-1 in the Army in 1960. One shot was 500 meters off hand.

Had a buddy, now deceased, who was a marksman for the marines. He said that once he learned how to shoot, the challenge was concentration, not skill.

Are you sure his name isn't Alvin York?

Foolproof!