In manufacturing consumables are categorised as non inventory items. . Therefore, they are expensed via the P&L. Therefore, in the item card is the general product posting group the same mapping as the P&L expense account or does it matter because they are going to be purchased via a P.O. account anyway. Or should the general product posting group stated as the same as all the other raw materials.
Secondly, is it absolutely necessary that you have to put consumables into a bill of materials? In many cases it's just extra admin to add into a BOM. Some manufacturers may not see the benefit of adding a consumable to a BOM when it is absolutely clear that you would need such a consumable in order to fulfil the production order anyway. e.g. screws.