Creating invoices doesn't allow for inventory items

Creating invoices doesn't allow for inventory items

If you are strictly using Invoicing (not a POS/Fullfillment order) there is no field for Item Code, only Description, GL Account, Qty, etc. There is no way to use Inventory when you create or edit an Invoice. Is this something that was left out purposely or am I missing something?

Many people invoice separate from inventory, and they don't want to be bothered with it. This is why we developed the POS -- (which can be saved as open account) and DOES tie in directly to the inventory. Orders can also be used.