1) Because of the deluge of college students. Many college educated people get jobs at Best Buy and retail outlets. Some of my high school friends are in situations like that. They assumed they would get a good job out of college, but that's what they get by getting a liberal arts degree and partying for 4 years. A 30,000-40,000 per year tuition, all down the drain.
2) Because a lot of job performance is measured by the market (i.e. startups). Getting a prestigious college degree doesn't necessarily get you the job needed and a lot of times you'll get beaten out by someone at a "less prestigious" school.
3) Many people getting a college, medical, or law degree should realize that if they're not at the top of their class, it's not necessarily guaranteed for them to get a great job. For a less prestigious university, it's even more so the case.
4) All of this will lead college counselors and the next generation of parents to advice people to get the most value for their money: i.e. a good education for a good price (i.e. not going to Harvard for Engineering, etc).