Calgary drivers have faith...

I came to the conclusion as I was driving around today that Calgary drivers must have a lot of faith... There were at least 4 times while I was driving around when drivers in front of me changed lanes in front of me without even looking in their mirrors or shoulder checking.  In most cases, had I not slammed on my brakes, I would have slammed into their car.  Thus, I have deduced that these drivers must make lane changes based purely on their faith that they aren't going to run into another car since they clearly aren't checking first...