I would agree that this has to do with marketing research, but I would say that the airlines could already use the amount of data they have on our normal trips to personalize offers, and I think they are not very good at that.

As a member of AAdvantage this registration thing is hysterical, but still I feel the output from their "research" seems pretty vague. They mainly copy the offers from UA or offers 2x or 3x the miles when promoting a new route and/or gets competition on an existing route.

Sometimes it is more a feeling that they want to avoid paying out a few extra bonus miles unless the card holder has actually done something.