Here's the demo:
Let's start by going to lan.com by entering the following URL:
Now, let's search for flights from Santiago (the capital) to Calama (the airport nearest to the Atacama desert).
Wow, US $48.25 for a one-way flight? Dude! I am so totally there! But wait a second, the site won't actually let me buy the tickets... it just says Estimado cliente, los vuelos escogidos no permiten ningún pago a través de LAN.com, which I gather is Chilean Spanish for "Sorry, dude."
So, let's try changing the URL to specify that we're in the USA:
And now let's try searching for the same flights:
Holy balls. The same flight now costs US $312? Amazing! That's a price premium of only 647%. Hell, you could fly to Calama and back three times for the same amount of money you'd pay if you bought the ticket outside of Chile.