What the fuck.
What does the kills/evilness curve look like? One kill is bad, 300k or so kills is bad, 5 billion kills is good?
Maybe it's 'different,' psychologically, because it's presumably random rather than targeted against specific groups of people. Or maybe it's 'different' the motivation is 'different'--reducing population across the board rather than eradicating a specific culture or ideology.
I use 'different' in quotes for a reason.