I didn't see anything on this subject, so here goes!
I was down there a few years back and was really surprised at the quality of the beer in the southern part of the country. Latin America is dominated by pissy tasting lagers, and around Santiago you do find Escudo a lot, which more or less fits into that category. It's serviceable, but nothing special.
However, there's a brewery called Kunstmann in Valdivia that does a great bock, and a pale ale called "Torobayo". In the far south, Punta Arenas' Cervecería Austral does a spectacular lager.
I had the same experience. It happens that there are a cluster of German expats that used to be in that area. (I heard there is also a BMW factory or something very German-like in those parts). I ended up reviewing a few of those brews and some quality beer bars that ended up on www.beeradvocate.com
I haven't found the Kuntsmann outside of Chile, but there are a few of the Chilean macro-lagers that you can purchase here in the states at places with larger inventory.