Good question.
I have never gotten a rabies vaccination. When I got my last round of shots a few years ago, the doctor told me that they could give me a rabies vaccination, but that if I were to be bitten by a rabid creature the treatment would be the same whether or not I got the vaccination-- so why bother? Now, I'm not sure if I just had a lazy doctor or they were out of the vaccination or what, but this made sense to me and I didn't get it. I also haven't noticed any rabid animals in the two years I've been working on this project... There are tons of stray dogs in town, that's for sure, but they're friendly and won't give you diseases. Maybe fleas, but probably not diseases.
Really, though, you should do what makes you comfortable. If you would feel more at ease having gotten the rabies vaccination, you should get it. If you ask a doctor who tells you something similar to what my doctor told me and you don't feel particularly keen on getting it, then maybe you don't need to.
But I guess I should ask: Has anyone else on this board that has been down to Ecuador before gotten the rabies vaccination?
Micah