My guess is that it is the pressure to conform working in multiple ways.

The reading of questions while the subject was screaming is acting in a way that seems like that it is a performative action of conforming to the pattern and that the failure of the pattern is caused by the answerer failing to conform to the pattern. That makes the shocks a punishment for failing to conform. The questioner has a facade of doing the right thing by going through the motions, even though they are breaking the rules by doing so, because if the other party were compliant that rule wouldn't have been broken. That the shocks were painful would feel appropriate to those who had a strong sense that nonconformity should be punished. It is less them following the rules and more them assuming the intent of the rules and permitting abuse because the intent was not their decision. It might make them less willing participants to the abuse and more 'not my problem' active participants.