No, the bus driver is a discrete person who you greeted and then thanked. Both parts of that are polite and help them enjoy their day: they are a worker who you saw and recognised. The pilots of an airliner can't hear you, they're still in the cockpit doing post flight stuff. You probably didn't see them before or during the flight unless its a really small plane or you're a time traveler and flying pre911. Sure it would be good to say thanks to the pilot if you see them but clapping isn't really that is it?