Mamlukes who are in front of you who try to merge onto a freeway a 25 miles per hour. The mix of 25 miles per hour with 70 mile per hour traffic is dangerous and if they want to risk their lives, well that is on them. But if you are behind them, your safety is in jeopardy. If you are on the onramp, mash that gas pedal.
Another pet peeve of mine is the smart alec physicists who think they know everything there is to know about the space/time continuum. Don’t get me started on these guys.