Normally in our scenarion BP will be created in CRM and replicated to ECC(ISU)
as i check in system there are about 40,506 SD consumers (table KNA1) where name (name1 / name2) is not maintained.
Some of these consumers are created during migration, however there are consumers created recently as well.
I have randomly checked for few consumers and all these consumers are of BP type is person.
For more information please find below screen shots.