Let's consider the assumption that between 36% and 45% of all undergrad students are slackers. Sure, a bunch of students aren't learning because they are slackers, but why there are SO MANY of them? Are there more slackers as a percentage of the population than in the past? Is the internet/cell-phone/facebook era changing the mentality of students to be more focused on the short term easiest/best solution? Or maybe the percent of slackers in the general populace is the same, but a much larger percentage of secondary students go on to undergrad. Well, why are so many more going on in school, especially those that are slackers? Parental/societal pressures might suggest that going to college is just "what you do" after high school. Or maybe peer pressure makes students continue in through school because their peers expect it of them. Perhaps it is sheer inertia that is the driving force; our slackers do whatever is the most expedient at the moment, so when the time comes they'd rather go to a generic college with an undecided major than to go and do something.
Or, (and I like this theory the most), students feel a need, from an economical perspective, to get a degree in order to get a job. And then they go to school, with the singular goal of earning that piece of paper so they can get a job. At this point, "slacker" has been forced into the role by going to school just to be able to get a job afterwards. It's a means to an end, and incidental value is just that. At this point, it isn't just the college's fault, but the general expectations of employers. Why do you require a college degree? Is knowing the theory essential to doing the work or save a substantial amount of training or ramp-up time?