It's not always people with industry jobs taking these part-time positions; there's a whole subculture of "freeway flyers" who are teaching at multiple community colleges, and sometimes lower-division classes at private universities, while trying to break into a full-time position. A few years after I was in his class, one chemistry professor I really enjoyed burned out from doing this and disappeared from all his classes in the middle of the semester. The replacement professor apparently wasn't at all prepared to step in, and the students had to petition the dean to have their grades thrown out and retake the class.

That's obviously the worst-case scenario I encountered, but I heard other tales of people like a math professor shuttling back and forth between Merced and Contra Costa counties every week. A biology professor I had was making a go of it doing half the week at Contra Costa campuses and half the week at USF, and told me her situation was not at all uncommon, even in the Bay Area. There's definitely a precariat associated with keeping the community college system going, which is a damned shame because it's the most accessible rung on the ladder. Perhaps the state will be able to do something about this, but it's understandably wise to be skeptical of statewide education initiatives in California.