Glaumring,
Allison sent them 1000 bushels of food on two occasions and that was before SA had even been to war with anyone. At that time Caerwyn had recently Federated with Astrum. Even then they wouldn't interact with anyone. I just assumed they were a very insular clique. What little bit I've learned IC and OOC about Asylon leads me to believe that the characters who would interact with others moved from Caerwyn to Asylon.
Insular... to a point. As I mentionned above, SA's role in Springdale's downfall played heavilly against it.