Originally Posted by davevi
I think you saw a different response (in the form of bonus miles) because you used another e-mail address. It is easy to track responses by e-mail address and their computers probably know that you've already received complaint bonus miles on your original e-mail address.
I highly doubt it - it's most likely by Worldperks account.
That said, I've sent lots of e-mails praising great employees when I run into them. I suspect once you're on this list you stay on it. As far as high fares, I don't think that matters either. Plenty of Y, Z, etc here.