The neat thing about a revovler is you can sneak up behind the bastard, screw the barrel into the back of his skull and pull the trigger and you could be sure that there would be a "bang". You could not say the same thing about a semi-auto.
Of course you could say, "The neat thing about a Barrett chambered in .338 Lapua is that you can stand a full mile away and still blow the bastard's brains out. You can't say the same thing about a revolver or a semi-auto pistol."
(Is that far enough away for you?)