Because they lack empathy, denigration of others is pure sport for narcissists. They readily enjoy gratifying themselves at the expense of others.
Extreme narcissistic malignancy characterizes the most disturbed characters among us. They wantonly use and abuse and feel entitled to do so.
Psychopaths know very well how most people think and respond, so it’s easy for them to manipulate others into making false assumptions about them and into a false of sympathy for them when they exhibit their heartless behavior.
Despite frequent social sanctions, aggressive personalities often persist in their aggressive defiance of society’s rules and limits.