No, not every record in Addressfinder has a DPID. Only those addresses that have a "delivery point" are assigned an ID. These DPID fields come from the New Zealand Post PAF database. They identify those addresses that can have mail delivered by a postie.
As a result, some of your address records in your CRM might not have a DPID against them. These will be for addresses that NZ Post do not deliver to. NZ Post typically do not deliver to addresses in the CBD of major cities, or to many rural destinations.
Within our system these addresses are sourced from Land Information New Zealand. The unique identifier for LINZ addresses is the aims_address_id field.
You can find out more about the various fields returned from Addressfinder in our API documentation.