True, but I have to question the alternate premise (that airlines arguably benefit more from selling a lot of points to outside groups and then letting folks exchange them for flights).

The internal card situation sort of makes sense insofar as I believe a given airline (or hotel) saves themselves some CC processing fees...but I find the 3-points-per-dollar standard which shows up most of the time to seem to be of dubious benefit to the issuing company (since the effective redemption value of those points generally only sits around 1% or so if the consumer redeems them for something like gift cards; from what I can tell, you can usually get more than that with a little bit of effort)...

...of course I'm also assuming logical behavior on the part of consumers, which is often a bit much to expect.