I definitely saw that in my undergraduate experience. I'd say a good 90% of my peers never went the extra mile on anything; if it wasn't going to be on an exam, you can bet they wouldn't bother studying it. When it came time to collaborate with them on projects, all they did was drag the serious students down. It was so frustrating by the time I graduated, but fortunately I had a really nice professor who worked with me to publish two papers on my independent study.
I really hope the slackers don't wind up with these mythical $130k a year jobs. I know I'll never be in a position to earn that much, because I'm more interested in research and theory. Which, to be honest, is what CS should really be about - these generic programming jobs are more or less software engineering, which has its own curriculum.