The credit card reps were actually at the event the day before the latest FTU. They seemed to say that churning is a tiny percentage of their customer base. And that as long as they were getting that customer's spend and not one of their competitors that that was what they most cared about.
They also are amassing a huge amount of data on all of their customers. And they are trying to figure out the best ways to exploit that data. Personalization of rewards seemed to be a big thing they are all aiming to start doing in the near term.
They also know what goes on. They read FT and MP. They read the blogs. They understand how their programs are being used by the tiny percentage of people who are playing the game. Out of all their millions of customers, surely the number really working the system and playing the game hard is a drop in the bucket.
With respect to affiliates, I can't really answer that. But I would be shocked if the big players didn't pay fairly close attention to how well their marketing is working and which affiliates are worth their while.
I don't really get all of the antipathy towards bloggers that keeps popping up here. It almost seems like a lot of envy to me.