score:4
Not really.
You can actually easily check where you can fly from Quito via the Airport's Website looks like you are able to fly to Guayaquil
Upvote:3
It's been more than one year since the original question, so I guess these flights were not available back then, but now LAN Chile offers direct flights from Santiago to Quito, but not the other way around. I checked the schedule on momondo for a few days in March 2015, here is an example.
One-way flights for those days cost around 647 euro, but it reduces to around 500 euro if you book a return flight, so even if you're not planning to take the flight back to Chile, it might make sense to book it that way. I haven't checked it separately, but sometimes you get a better deal if you book open-jaw tickets rather than buying a one-way ticket, e.g. Santiago-Quito-Lima may be cheaper than Santiago-Quito for certain dates.