Well, "I understand" doesn't mean much here, now does it?!
I understand how many people who are unable to feel the pain of others, including the pain that they cause to others, such as Sociopaths, Psychopaths, Narcissists and so on will, if they think they can get away with it, not at all refrain from causing huge suffering to countless other people if they themselves come out of it better.
And it's all irrelevant: whilst it's psychologically easier for them to cause suffering to others (as they feel no guilt) as individuals with agency they're still the ones who choose to or not-to cause suffering to others: if they act thus they should be punished, if they don't they should not.
The only thing the "understanding" brings is putting such people higher up the list for surveillance and as suspect when it comes to detecting and punishing the harming of others than people who psychologically find it a lot harder act so because, unlike this group, they feel guilt.