Tesla's (and increasingly all cars) are software with attached motors and they don't need to seize them physically to take them. Or disable supercharging, etc.
Just like your fridge may not dispense water if you buy the wrong filter. Or your random IOT enabled device will refuse to work if you don't let it phone home with surveillance data.
It'll probably need new legislation to protect consumers.
Although I was joking about the SEC thing, what happens if Elon get's a grudge? Some would say it's your fault for buying the car, but some guarantees for consumers are useful.
