You are correct. People do that because they saw it done that way in a Cisco doc and have not thought about it much.
There is one valid use of LAA though.
Say you are queuing to some agents in a skill group but you also have some training agents in another skill group. You don't want to queue to these agents, because they are in training and you don't want to bombard them. But when one is available and a call arrives, you want to give them a call. I have had cases when there has been quite a hierarchy of these.
Regards,
Geoff