See this https://shops.audi.com/en_GB/web/zubehoer/p/retrofit-solutio... for example. I can only assume it's resistive, since it doesn't start the engine - but it might be a system for running the AC heatpump without engine, maybe. Also now that I think of it, window defrost is resistive.
I would guess system like this would be rare in US, because you are allowed to have remote start on your cars.
Electric window defrosters are really low wattage - because its just trying to raise the temperature of the surface of the glass by a few degrees. Generally IIRC no more than 25-30a - which is a fair bit on a car with a 100a alternator - but less than for example the blower for the air conditioner.
I never thought I'd see the return of the gasoline heater. I wonder if its offered in the states.
I would guess system like this would be rare in US, because you are allowed to have remote start on your cars.
edit: never mind, it burns fuel https://www.auditech.org/acont-1427.html