When I was in college the one adjunct professor I had worked at Allison Transmission for his full time job. What is this guy’s field? I think colleges should have to disclose upfront that certain degrees limit your employment opportunities to professor, or grocery clerk.
A few of the adjuncts I had were military instructors at the nearby Air Force Institute of Technology (and some of our full time professors served as adjuncts at AFIT). It was fun to give them some crap when they were running late and didn't have time to change into their civies. Other adjunct instructors (not PhDs) worked in industry and taught some night classes including one guy who worked down the hall from me during the day.
Maybe it was just because there was a greater demand for engineers in industry than philosophers, but I don't remember any crying about low pay.