Default Owner on Account object record after turning off making this field required

He have determined that we would like to take advantange of not having the requirement of a record to have an owner assigned when being imported from our existing EBS system.  From a business perspective this is valuable in that we will no longer need to classify to which sales person or territory a customer is assigned to in our EBS system and this information can be maintained from within CRM. We are a global business and we have one set of books for the US but a single ship to could in fact be serviced by muliple sales reps based