plus the ego of these people is unreal, demanding they be called DOCTOR BlahBlah simple because of a piece of paper.
First of all, there's a difference between a "PhD" and the professional doctorate, or what's more commonly known as an M.D. (your doctor), D.V.M. (your vet), D.D.S. (your dentist), etc.
A PhD is primarily a research degree, meaning that the holder has not only "mastered" the content of their discipline, but is also trained in the skills required to research and acquire new knowledge. It requires a lot of content in the areas of research methods and statistics.
Some professions have difficulty attracting new faculty because the people who have the talent and/or the degree in hand can make LOTS more money in their respective industries than they can possibly make in academia. I am an example of this issue. I am an R.N. with a PhD in Nursing Administration, making me as rare as hen's teeth, but horribly underpaid in my university position compared to what I could make in a hospital setting.
I do research and teaching related to health care informatics and patient outcomes, but I could make approximately double what I do now if I was employed in a management position in a hospital setting.
I actually meant to reply to Chode on this.
He thought about teaching but shelved the idea after exploring it. Too PC for him.