Here you can obtain a "passport" book for "Revolucion de la Cuchara" (Revolution of the Spoon). This book & associated web-site enable you to find a participating restaurant or veg-friendly establishment & to get a discount there. It is a slowly growing movement across South America (traditionally very meat oriented cultures.) We found a Govinda's (Hari Krishna centres serving food) in La Serena & Temuco as well in Chile. Ask as you go, they are often not "open" to the public & you have to knock on closed doors to get in.
Cons: not always easy to find