Just an update. I had no difficulties booking and paying for internal Chilean flights on latam.cl using Chrome Incognito. I actually did a multi-city booking: it generated the same cheap fares that Latam gives you when you book a simple roundtrip. Free seat assignments, too (I can't remember if that's customary these days in Chile).

The fares seemed remarkably cheap: about US$35 per segment. I'm not sure if that's a special sale. On their website, Sky is advertising a special 4-day sale in that price range so perhaps Latam is matching. For the flight times I needed, Latam was cheaper than Sky.

I did compare these prices to Latam's USA site, and the fares were 3x there.

As a heads up, I understand that a new ultra low cost airline is starting up in Chile this year called JetSmart. This seems crazy to me. Domestic Chilean airfares always seem cheap -- at least if you buy them in Chile. Who needs an "ultra low cost carrier" when Latam is US$35?

https://www.thestreet.com/story/1399...-to-chile.html