Photojournalist here, shooting spot and breaking news and features for newspapers, magazines and online media on assignment and for the wire service-----lived on and off in Chile for months and years in Chile since 1984.
For a PJ specializing in Latin America, Chile would be an excellent choice in location----even living remotely in Patagonia as you can fly north or south and get out to where you want to be. Working as a photographer in Chile there would be a certain amount of business but probably not much. In regard to shooting for foreign media on assignment with shots on travel, news etc, there would be a certain amount there as well----probably core work would be national and municipal tourism agencies too but would take a while to build it up----If you are at the right spot, at the right time, there could be Chilean newspaper and magazine work but it would be pretty sparse but more on that later
Maybe some NGO work and large national corporate accounts as well as product or interest specific businesses outside of Chile to get into to but will always be a mixed bag of things across the board----but really in regard to working photographers, commercial, advertising and news, its kinda of the same no matter where you are----a definite mixed bag of work.
Living in Chile and just shooting stock photos, forget it but reading through the posts you are clear on that-----its just the reality of the image business, again, no matter where you are.
There is the visa thing and paying taxes but its a different road for everyone and one taken once you decide you are to settle here. One issue would be, no matter you live in Chile, would be keeping equipment safe from theft for even a short trip to the market let alone being gone on assignment for a month. I would not trust any delivery of equipment where they are sending it to you----so you would have to get everything in the USA personally no matter what.
There is a photo agency in Chile, Agencia Uno, (http://agenciauno.cl
) and they supply photos domestically and outside of Chile with a pretty good stable of photographers-----have no idea what the pay or how they are-----
In regard to shooting in Chile-----the chance of a snatch and grab is unlikely except in the dodgey areas of Santiago or in something like a heavy protest where somebody can get at you and get away in the mayhem. Shooting with Chilean news guys, they are a tight bunch so there is protection in that for sure-----not like Colombia or Brazil or Argentina in that way with the moto snatch and grab----but don't think that you would not be a target pretty quick for an inspired thief to figure out what your photo rig is worth and you have it at home or in your car----even if you have a strong lock box in place within the house, the bad guys will still cause a lot of damage getting at it and they won't just try once and not come back every now and then for another try.
There are a lot of stories going on in Chile and its not well covered but someone clever could fish them up over time----There was a Chilean shooter doing a lot of work with great stories about 15 years ago but he is mostly international now and shoots a lot for the NY Times and others-----too bad, he was really good-----Chile needs a go to photographer to provide that content but again it would be a mixed bag with it to start and could take maybe 10 years to be that guy and a lot of work and a lot of money to get there.