The incentives in college have always been in alignment, because there is so much interesting stuff going on (at universities worth their name) on campus, both in the academic and social spheres (visiting scholars, entrepreneurs, conferences, reading groups, debating, dinners, balls, parties, even fraternities, and foremostly time for real conversations with close friends), that finishing work efficiently always has had its own payoffs.
For all the talk about on-line degrees, I don't see them being a good replacement, unless as the cheap/distance option (makes more sense where tuition is high such as in the US), or for mature students with a job/family on the side.
Nothing can replace the full university experience (perhaps until somebody boots up a proper Matrix).
College is not just about book-knowledge, but also about being immersed in a new environment, meeting new people and developing new skills.
Naturally all this can be done in ones sleepy home-village, or on the 10/5-6 city job as well, but very few people find the time, or do the root-cutting necessary to be able to do so.