I am very interested in the responses to this question.

I just forwarded this question to airline industry friends of mine, so I will see what they say, as they are able to respond.

From what I do know(not much, I know, ha ha),
airlines keep a file on people...You send them letters, can be comments when talking to reservations(yes, they do record those), travel habits, etc. Do you find it a coincidence that you will get e-mail/physical mail promoting a certain destination that you always go to?

Anyway, there was a letter in a business travel magazine from a frequent flyer on Air Canada. She complained, probably justified. When they would swipe her boarding pass at the gate, all kinds of bad comments would come up on the screen, like she complains, etc... then would get bad treatment... They would see her as a problem pax, and would brush her off. My friend somehow got a black mark with United, wasn't good. They didn't want to sell him tickets, and this was long ago, before all the security idiocy.

One reason I don't always complain to an airline, even if I feel justified. You might like the extra 5K miles they give you for griping, but it gets recorded in the system. That I can promise you. Too many of those, you are a problem passenger...

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Michael
AA PLT,1 MLN Miles+
HH GLD, SCI GLD, MM SIL
LE PRESIDENT ETERNEL DE CAMAIR-CAMEROUN AIRLINES