WaldoAR15 --- even though CB and CI are sister sites (or is CI the parent site?) ... they are actually two seperate companies, and and are run independant of each other.
Cigars such as PAM's, are often limited release and can be hard to get in any significant volume ... so maybe it's just that they don't get enough of them in to place them as a regular offering on their parent site ... and prefer to offer up what they do get in on their auction site.
Not knowing the finer details on how they run these two businesses, that is just my educated guess ...