I've worked on factory floors; the worst cubicle in my experience is a more comfortable (and safer) place than any factory floor I've seen.

"White|Blue" collar is not about how one is paid -- engineering aides, drafters (draftmen and draftwomen), computers (it was once a job title, not a piece of hardware), etc were "white" collar. I would classify "white" collar workers as those whose output is not an object, but information. Of course, some workers fall outside the two camps, and some wander back and forth.