Like Danny said, there is no really good answer. But, I truly believe that the schools have either requested to be placed in a certain region, or accepted their placement without appealing it. I really doubt that any school is forced to be put in a region when there is reasonable option.
Also, there is NO requirement to play teams in your home region. There are District requirements, but even that has pathway to an exception.
I honestly don’t mean for this to sound smart ***, but if a school doesn’t want to travel 4 1/2 hours away, then don’t schedule a team that far away. I’ll agree with you, that is a long time to ride a bus. It severely diminishes the number of parents and fans that can attend. And it often makes it difficult to impossible to take the band, and sometimes even the cheerleaders.
To illustrate what extreme travel does, in 2015 Arcadia traveled to Clarke County for the first playoff game. A friend at that game said that they counted 7 people on the visitors side, and that included the school bus drivers. He also said that the CC fans actually cheered for the kids from Arcadia when they took the field. Incidentally, there wasn’t much to cheer for after that. I think the final score was 60-6?