I am a gardener and that is definitely blue collar :)

my father once said that the sole purpose of college or education was to teach you how to learn
I have seen a more cynical take that university is a way of proving who is a conformist. But my university gives all graduates a higher degree three years after they graduate without taking any further courses or exams. Many people consider this outrageous, but actually I think it is fair - once you are set on the right path of learning it becomes a lifelong thing that you do for yourself.

And a lot of nurses
Maybe it was the 'cross' part in the name that attracted them :D