Agreed, I expected to see a credit to a balance sheet inventory account and a debit to cost of goods sold on processing a sale as well... But that doesn't seem to happen. Try using page / card / screen 'Post Inventory Cost to G/L', you may well find this makes the missing transactions appear in the GL.
I think what you are seeing is 'normal functionality', the system recognises the sale but not the cost of the sale... you have to come along later and tell the system you are ready to recognise the cost of the sale as a separate step. It seems an odd way of doing things to me, perhaps there is a logic?