I asked them about this, here is the scoop:

1 - inbound for non-eGate holders, is always by officer
2 - at T1, foreigners can use the automated system to leave (since they have already been fingerprinted and photographed coming in) - these are separate gates
3 - eventually, the goal is to integrate this functionality on the outbound eGates instead separate gates
4 - no plan to allow inbound non-eGate passengers to use the automated system