The author of "Traffic: Why We Drive the Way We Do (and What It Says About Us)" has several stories about inattention blindness... including classic tales of drivers plowing right into large garbage trucks in broad daylight, and police cars with full emergency lighting turned on.
The fact is, all too often, drivers are not paying attention, drive too fast for the conditions, and tend to apply power when they should be slowing down and evaluating.
No doubt rachel120, you were quite visible, had the driver actually been looking, rather than simply staring out the window.