Easier to haul my luggage on a train designed for that purpose than take a car and spend longer parking it than the entire train journey. I live 10 minutes from Gatwick, have never driven there, and don’t understand why anyone would want to if there’s any alternative.

Taxis I understand.

Same, I also live very close to Gatwick, the train is about 4 stops for me and puts me right at the terminal. Zero reason to drive.