Nope. They don't. And don't expect them to. They hit large cars on a regular basis. What makes you think they will see you on your bike? That's the way I ride. Every side road I come to, I'm looking behind me in case someone is coming to make a right turn into it. (and into me) Then I'm looking up that road to make sure someone isn't coming down it and not stopping at the sign. Cars coming out of a driveway... don't even bother to assume they see you. Even if they do, they still seem to back out.

Think about this: Have you ever been riding along at a good rate of speed and see something in the road. You keep looking at it so you can avoid it and what do you do? You run it over. You will go where you are looking no matter how hard you try. Drivers in cars are the same way. If they see you or don't, the odds are they will tag you. Be your own advocate for personal safety. You have no blind spots. Anticipate and adjust. You will live longer and better.

Am I saying be paranoid when you're riding? Well, only a little. If we aren't enjoying the ride, then what's the point? Learning to balance the freedom and fun of riding with the dangers of the motorized population around you is essential. Or... just stick to the paths. Of course then, you have children, unleashed dogs or errant little old lady motorists backing up in Prius' who don't even know they aren't on a road anymore...

Good luck and stay safe.