Is "Country" really mandatory in BP addresses?

Good day dear experts!

I need an answer to a seemingly easy issue.

Scenario: CRM 5.0, EP 7.0, NW 2004s

Our System Integrator insists that the Country of the BP's address MUST be mandatory otherwise there will be trouble in data quality, relationships, etc.

On the contrary, we are asking them to make the Country optional because the data source (old CRM) has few country data. The migration would leave out lots of partners if the Country data was left compulsory.

The question: I have seen that, in the PCUI, you can make the country as NON-compulsory.

In "Maintain Business Partner", there is no special need on Country data.

Would anybody see any counter-effect if we left the Country as non-compulsory?

Thanks!

Riccardo