I had an issue where the customer team in Brazil pointed me to a service team in Europe, since my account was opened with my belgian address and passport data from older times. I asked them to change it to my brazilian address, which involved sending a copy of my brazilian document & CPF.
No benefit other than being able to use regional call centers and elite service desks. (That said, I think it was a one-off issue with a specific employee, who was not in the mood to deal with my case. I had used the brazilian elite desk before without any issues....)