No doubt, but players goals tend to be guided by gameplay mechanics.
For example, if sieging another clans town costs a tremendous amount of resources, but provides no possible reward than the joy of victory, you will see this as a very rare and potentially unviable endgame activity.
Whereas if you can freely plunder your enemies stores after victory, and you are actually in need of these resources because the economy has sufficient item sinks, you will see sieges as a common and profitable lategame goal.
How they decide to structure economic incentives for lategame activities, and the economy, will truly shape what people do in the lategame. I tried to ask the what vision they had in a single sentence.
I hope conveyed the real depth of the question