The academic endeavor at all universities relies on mutual trust between faculty and students. Students and faculty are responsible to the academic community for the preparation and presentation of work representing their own efforts. When students commit acts of academic misconduct, they are sometimes surprised at the strong reaction of faculty members. To begin with, faculty assume that their students are honest and such acts are a breach of trust. Some forms of academic misconduct constitute theft of ideas, and from the point of view of faculty members, whose life work is creating and disseminating ideas, stealing someone's ideas is equivalent to stealing their money or their car.
Here's a link to a good article about why integrity is important in college and in the world beyond (note -- this link will launch Adobe Acrobat): http://sja.ucdavis.edu/files/WhyInteg.pdf