People in rural areas or smaller communities are sent to Anchorage for: 1) mental health treatment,  2) substance abuse treatment, 3) for medical treatment,  4) young teens or kids are sent there for specialized foster care or residential  care.
That is because those services are NOT available in their communities. Sometimes, they get up and walk away from those places. Most do not want to be there.
Our tribal health clinic refuses to pay for the in-patient hospital unless it is an emergency. As soon as they can send them to Anchorage they do. We want them to stay here but it's all about $$$. A child broke his arm and despite the fact we happen to now have one of the best top ten orthopedic surgeons in the US here, child and his mother had to fly to Anchorage to have the surgery there.
Kids in treatment need to be where their families or extended families can participate in their treatment. Our state10 bed facility was closed last year. Anchorage is greedy about getting the grant $.