I noted that also. When I went to college, all professors, assistant professors, and associate professors had doctorate degrees. Adjunct professors, instructors, and teaching assistants held masters degrees. There were exceptions, but they tended to be in areas where the highest degree awarded was a masters degree such as an MA in Architecture and Design.
I also noted that his interest is in "socio-linguistic theory," which means that Noam Chomski is his God. Pathetic.
For community colleges, you do not need a PhD to teach. In some cases a BA or a BS is sufficient.