"There is just a bare anode current collector without anode materials?"

Correct, anode free cells refer to the in-situ formation of the anode material on charge derived solely from the lithium intercalated into whatever cathode they have chosen for this particular cell. Where the anode should be prior to charging is just a current collector which has perhaps undergone some surface modification to encourage good formation of the anode material (probably lithium metal). This strategy is a means of increasing the gravimetric capacity of the cell. When you form a lithium metal anode in situ like this, you necessarily do not have excess lithium metal that is basically just sitting in the cell doing nothing but weighing it down.