College is the easiest time in a runner's life. Easier than hs, easier than a career. You have to go to class, do your classwork, and study enough to pass. This takes maybe 40 hours a week, but usually less (lets face it, 98% of runners are more interested in running or reading letsrun than doing intensive research and are scraping together their papers in the week before they're due). Anyways, 40 hours spread across 7 days provides a lot more time than 40 hours spread over 5. Think about how much better your training would be if you had an extra 2 hours a day. Then commute. The average worker commutes 60-90 hours a day, the college runner commutes 15-30 mins a day. Now you've got 3 hours a day over a 40 hour a week worker. Ya, technically the college runner has less time on the weekend, but lets face it, the post college worker just spends that extra 6 hours cleaning, doing chores, or watching tv.
Now lets move away from time and go to access to facilities. Trails and tracks are usually right there on campus. Most campuses have a couple mile loop around campus that has no traffic very early in the morning and/or a mile or so loop around the athletic fields, maybe a golf course on campus, etc. The post college worker has to hope the local hs's track is unlocked (prob not), there isn't a practice or game going on (there almost always is a practice until like 8 at night and games until who knows when). You could run on the golf course on campus just fine as a student, but the local golf club near your home sure as hell isn't letting runners on, even when they're closed. For 90% of Americans, trails are a drive away instead of a couple miles run too, even more time the college runner has over the worker.
The only advantage the worker has is money from a job, which is quickly diminished by bills, social ocassions, which are no longer free or minimum cost, and race entry fees.
I enjoy running now, but I look back at college, 5 years ago and know that its nowhere near as good.