Inconsiderate Drivers Frustrate Me

Okay, so I'm driving home from work today and came across the following scenario:

I'm sitting at a red light, going straight, and waiting for it to turn green. Over the radio, I heard a siren from somewhere. I turned the radio down and started looking around, and saw an ambulance coming down the street from my right, towards the intersection. As the ambulance got closer, the light for vehicles going in the opposite direction as me got their green light - the two straight lanes and the left hand turn lane got the green turn arrow - while my side still had a red light.

As I watched the ambulance get to the intersection, I noticed the driver in the car across the intersection, facing my direction and waiting to turn left. This driver also noticed the approaching ambulance and despite having the green arrow, the driver waited, making sure he was out of the way so the ambulance could get through the intersection. As he waited, the vehicle behind him became inpatient and went around the first car so he could go ahead and turn left. Around as in crossing the center line and going in the wrong lane of traffic before cutting across to make their turn.

The first thing that bothered me was the nerve of that second driver - to pull out into the wrong lane and create a dangerous situation just to make their turn. What made it worse, was because of that second car's actions, the car behind him DID THE SAME THING. The oncoming ambulance was turning right - to eventually go in the same direction I was heading. As the ambulance came to the intersection and prepared to turn right, the driver was alert enough to see what these two idiots were doing.

Because those two vehicles had cut across the center line and into the wrong side of traffic, the ambulance driver had to come to a complete stop and wait for those two vehicles to complete their turns and get out of the wrong lane of traffic. Thankfully the ambulance driver was alert enough to notice what was going on or there may have been a need for a couple more of his coworkers.

The whole situation just irritated me that these two idiots couldn't wait. Maybe they didn't hear/see the ambulance coming, but to me that's irrelevant. They still created a dangerous situation by crossing into the wrong lane. Were they in that big of a hurry? Instead they had to make their turn and get going, causing the ambulance to stop and lose time on their way to either meet an injured victim or get an injured victim to the hospital. Impatient and inconsiderate.