I just want to share my experience to make sure it doesn’t happen to other people.
In the Quito bus terminal, there are thieves that systematically rob people when the busses are waiting to leave. One acts as he works for the bus company, checks the ticket and all. Two guys work with him and will rob the valuables from the seat behind you while he distracts you. It was a combination of them being good at what they do and me being very tired and not alert. I had my bag where I could see it, I never thought they could open it and take the stuff without me noticing anything!
There were 5 foreigners on that bus and all were robbed.
Please don’t comment with what I should and should not have done, I am already pretty beaten up.
What I have learned: better wear money belts on long journeys, the only place where the bag should stay is on your lap, never trust anyone blindly…