It's hard to condone the act of murder in any situation, and Zardoff's hunting of human prey is simply an act of cold-blooded murder. His reasons for devising a new game, with human beings as the hunted, are unjustifiable. Hunting animals had become a "bore," and he was suffering from "ennui"; animals offered him "no thrill... no real danger." The fact the men he hunted were
"... the scum of the earth: sailors from tramp ships--lassars, blacks, Chinese, whites, mongrels--"
did not give him the right to kill them, nor did his giving them a head start (or the option of dying at the hands of Ivan) make the game any more equitable for the prisoners. Rainsford summed it up when he said,
"But they are men..."
As for Zaroff's refined behavior in clothing, food and drink, it could be argued that he enjoyed these civilized facets of his life, but his barbaric acts in the jungle of his island showed the truly uncivilized side of his nature.