Factually speaking, it is not irresponsible. Many driving schools teach braking approaching “stale greens” and bus drivers and truck drivers are always supposed to do this because they’re ferrying so much mass that they don’t want to try to brake suddenly and inadvertently running reds are bad when your job is on the line. They then tend to port this over to their day driving as it becomes ingrained habit. It’s the safer way to drive and realistically your brief pause at a red light shouldn’t have any bearing on your day-to-day life. Stop and smell the roses idling diesel fumes!
Now saying that I admit sometimes it annoys as well, because I’m a gigantic hypocrite. The difference is I recognize that’s on me - they’re not actually doing anything wrong 
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