..and you can also use a Pchannel FET for highside switching, then you don`t need a charge pump.
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N-Ch FETs are more common and easy to drive. There are logic level MOSFETS that can be directely driven by a 5V or even 3.3V logic output.
But in cars you have a common "minus" system. All the chassis is connected to minus. Here it makes more sense to switch the high side. One wire swiched high side to load, and return via chassis.