These employees can get to know a student far better than any recruiter could, and have an excellent sense of whether or not the candidate would make a good fit for your organization and it culture. This type of relationship is very effective at the graduate level. I even know of cases where an employee recruited a professor to a full time position in his company. If this is worked well, an employee can be both an employee and a professor and serve both roles effectively. If both, they are excellent recruiters.
Many schools can use an extra hard at running a lab or lecturing to a senior class.
Many schools that I am affiliated with actively recruit employees of large companies to act as adjunct faculty or as guest lecturers. Some companies hire and train students to be scouts to constantly look for fellow students that would make good employees. They get a small bonus for each student they recommend and who the company eventually hires. Some companies have developed a similar relationship with professors and ask them to recommend good students and help convince the students about the quality of the company. These relationships require nurturing and may take you and your company to places never dreamed of.