I hate the trope of the selfish hero (most often American) who will kill, maim, and abandon anyone who isn't in their inner circle (family, love interest, member of their unit). It grates even more when anyone who does perform an altruistic act is almost immediately punished, bitten, shot, or betrayed for being stupid enough to be kind. It says a lot about the psyche of the American viewers but as. Brit I fund myself hoping the hero gets killed sooner rather than later.
Like Gwen Cooper in Torchwood: Miracle Day? I hated that too.