I think we're in agreement about what the rewards system is. I'm just saying that the side effect of getting points-users really invested in using points is a second layer of the scam. Obviously it is good for the credit card issuers if most users don't use their points, that's free money for them.
> So anything that helps consumers make the most of these points, I think, should help reduce these companies' profits.
I mean, no - the answer isn't "try to bleed them dry by exploiting points," any more than "launch barrels of water into space" is the answer to sea level rise. Use your points while you have them, but the correct solution for societal good is to ban the whole system.
I think banning the whole system isn't going to do anything but improve profits for them (maybe; they're doing the points systems because they think it'll convince customers to use them instead of a competitor). I think if you really want to fix the problem, you need more regulation so that prices are kept low. So, for instance, for credit card points, you need regulation forcing the CC companies to lower the fees they charge to merchants, like they do in Europe.
Oh yes, I agree that regulation would need to be more robust to future exploitation. But banning the points system isn't intrinsically going to increase their profits, or they wouldn't be running it in the first place.