1. It is a fact that college graduates on average make much more than non-college graduates (http://usgovinfo.about.com/od/moneym...ndearnings.htm).
2. Society as a whole encourages higher education as a means of bettering ones' position in life, based on the above fact.
3. Therefore, it is reasonable that the vast majority college students are acquiring education with better employment opportunities in mind. It's not a matter of "guarantees", but of statistical probability.
4. With such being the case, educators have the moral responsibility to stay aprised,, and inform their students, of the job situation (statistical probability) for the major they are pursuing. To do anything less is negligence at best, highway robbery at worst. If these students were your children, would you tell them in no uncertain terms of the reality of the job situation? That's really what it comes down to. Professional honesty.