There’s a lot of desert between Riverside, CA and Phoenix, AZ.
If you live in the Poconos and are a teacher, you might commute to New Jersey or New York State to get an extra $20K/year. So Pocono school districts have to pay more. And Scranton has to pay more. And so does Hazleton. And so does Harrisburg.
Riverside is just too far away from Phoenix for a tolerable commute.
There is no limit on the number of teachers that can live in the Poconos. Both New York and Pennsylvania teachers could live there.