Honestly, they give us a well thought out, intelligent show, and there's hosts of people crying and moaning because they're being asked to break the ultimate commandment of television: Thou shalt not use your brain.
OK, so Heroes isn't going to hold your hand and spoon feed you through each episode. They have 3 dimensional characters who act like humans. Why are you not a killer? Because you've never been in a situation where it became life or death, future or no future, and your only option you seemed able to take was to kill. A big part of crime and acting "bad" is just that life was bluffing, and you just lost your hand, it's not all about evil plotting and laughing.