Also hand-woven traditional scarves, to reference a certain podcast. Sure, you can replicate them, but then it's not genuine anymore.
More seriously, the basic answer for the Federation in particular would be "amounts of energy". Voyager uses exactly that, with minor but consistent references to 'replicator rations' because they're limiting the total energy usage of the ship.
More seriously, the basic answer for the Federation in particular would be "amounts of energy". Voyager uses exactly that, with minor but consistent references to 'replicator rations' because they're limiting the total energy usage of the ship.