"Drivers shouldn't have to pay to fill up their cars. Instead, they should owe the cost of the tank of fuel, which should be charged to them on a journey-by-journey basis and they're not allowed to leave the car until they've paid by coins in their dashboard".
Oh for such a world. Well, probably not as I use my car occasionally when a bus is not available and wouldn't want to have to be sure I had sufficient coinage to ensure I'd not be held prisoner in it when I arrived at my destination.
But her outburst shone a light (for me, at least) as to why some people begrudge travelling on buses: cost. They consider a £3.50 day ticket as 'extortionate', when they'd commute to work and pay double that in petrol. Charge them on a journey-by-journey basis and soon they'd realise that £3.50 on the bus is actually 'quite reasonable' or at least 'comparable'.
Not that this will ever happen. Woe betide any government that tries to inconvenience our use of the private motor car.
But it would be good to see dashboard computers display how much the journey undertaken had cost the driver, in pounds and pence. They technology is there, though the driver would need to state how much the fuel cost, then the car computer would do the rest.