People who get mad at you for calling out their idiocy and stupid behavior. I'm driving through an intersection with a green light, and a guy coming from the right (with a red light) has to slam on his brakes halfway through the intersection to avoid hitting me. He gives me the finger when I honk. What?! I'm a bad guy for honking at you for running a red light?
People who recline their seat on an airplane, even though they're not sleeping. Look, this isn't your personal lounge. Reclining your seat might make you more comfortable, but it makes me less comfortable. Making yourself feel better at the expense of others is wrong. I wouldn't even mind it if you're going to snooze, but reclining just to read? Jerk.
Note: for the record, pedophiles, rapists and mass murderers are not people, and therefore don't qualify for my rankings.