Then Superman and Lois Lane would both be completely immoral, insane and completely without any sort of humanity whatsoever. And I'm pretty sure that was not how that scene was meant to be taken. You kill two people and let a third die and it's time for laughs? When they were completely neutralized and posed no threat? It's not like Bond's gallows humor after he kills, and besides, Bond is supposed to be a killer-and not a killing only when necessary killer, either.