why are airfares more expensive going to small cities on smaller planes?

I can fly roundtrip on a jet from Atl to Vegas or Miami for $200. But if I fly on a smaller plane to Raleigh, NC it costs $400. why is that?

Public Comments

1. It costs about the same for the airline for a flight with 300 people as a flight with 75. So essentially, the fewer people the more each has to pay
2. Landing costs are high and when only small planes can land that means fewer passengers so they have to defer larger amounts to less customers. Basic supply and demand keeps it alive though doesn't it?
3. Its a complicated market. It all depends on what airlines fly that flight. If alot of airlines fly Miami-Atlanta than fares are cheaper. But if only one airline flys Miami-Atlanta they can sell for a higher price. Also depends on where you are going and if it is a high demand part of the year etc.. Lots of things go into selling tickets for flights. But smaller planes cost less to run. Less fuel etc...