I thought the same when I checked in in Paris for an AF flight to AMS, printed boarding pass and luggage labels only to hand them over to an agent who checked our ID!
Having said that I found the Air New Zealand domestic system quite good. Get boarding passes and luggage labels and then just place them on a conveyor belts and that is it. There were a couple of staff floor walking and helping people if they needed it. That was a few years back now, might have changed.