The High School League mandates that all games use officials that are certified by the League office. I can see the point...with nobody really regulating who is a "qualified" volunteer, who is to say that all officials at the game are making knowledgeable, unbiased decisions? And every member of the officiating crew--even someone volunteering to run lines--is responsible for making some decisions; otherwise they wouldn't need to be there in the first place.
As much as I prefer a three-man system whenever possible, in a match that can determine playoff eligibility--or even the average match in which player safety is always a concern--I would rather have two trained, certified, and unbiased officials with no connection to either team, than to have an uncertain quantity pulled from someone's fan base making decisions on the field.