In the event of an accident, there are many cases where, if you are wearing your seatbelt, being physically held into the driver's seat will allow you to maintain control for longer, or even regain control, when you otherwise would not.

I'm from a place with a LOT of rain, and a LOT of ice, and I have personally been in three auto accidents at at least 30 mph. We are taught the simple truth that we will be in accidents, and that learning to mitigate them, when prevention is impossible, is paramount. In one case, the car literally ended up doing a 180, but my father was able to regain control afterward and prevent us from running into a cliff wall. He would have been unquestionably incapable of doing so had he not been wearing his seatbelt. To this day, it is the greatest example of alacrity in a crisis that I've been privileged to witness. In another, my mother was able to maintain control as we skidded off the road from a sudden hydroplane, managing to make it into a farmer's field, rather than flipping the car. In the third, black ice prevented me from stopping as I traveled downhill (the cop who responded nearly biffed it getting put of his car, the ice was so thin and invisible it looked like nothing but mist), and the person in front of me, stopped in the middle of the road, did not have their turn signal on. I had just started to pull to get around them, forcing the belt to cut into my shoulder, when I realised they had just started turning the same direction without a signal. Had I been flung by the force of my initial swerve and unable to maintain control, I would have plowed into their driver door, but instead, I was able to just barely course-correct to the right, skimming their right rear bumper instead. Among the three accidents, no injuries, and the only one of the three which involved a collision with anything thicker than a few stalks of wheat was mine, which nearly ended with me t-boning the idiot in front of me.

Get over yourself, because there are damn important reasons you need to care, in spite of the fact you appear to value your own life so little.