You are missing the point that it is true that robberies GENERALLY don't involve torture. That is 100% irrefutably true.
Nor do most tortures generally involve robbery.
You are losing a good argument by not concentrating on the point made by your antagonists which is not supportive of the victims of SSAD.
The converse of the other argument is not so easily dismissed. How often do rapists steal a purse or a "souvenir"?
Torture is a crime of sadism (which is what the 13 year old endured before his death).
It is also a component to rape (since sexual assault is violating someone without consent).
Can you believe this? I should probably learn some sort of a lesson here...