Should FPCC0002 be inserting an entry into DFKKCOH for 0 balance?

Hello, we're new to this and we have thousands of entries in DFKKCOH for customers with 0 balance. (The line item table that is passed to the custom exit is 0.) We discovered this because our vendor's code was creating a short dump because they had a bad "select all for empty table" entry. We fixed this, but the question is now, why are those entries in the DFKKCOH table at all? We don't print bills for 0 amounts.

FPCC002 is SAP standard code. Should this code put these 0 balance entries in the table at all? And is there a way to stop this?

Any info on this will be highly appreaciated.

Thanks.