Except for the scores of other top level professional motorsports that have no fuel flow or allocation rules. These rules are specific to F1. It's window dressing to appear to be eco-friendly and also a way to enforce a power equalizer with regards to the design. The real carbon impact are the ships that transport the bulk cargo for the flyaways, the chartered freight flights for the air cargo, the fleets of trucks that transport the gear and motorhomes during the European swing and the fuel burned to fly the commercial flights to get the crew and spectators to an event. The fuel burned and carbon emitted from the race cars are but a pimple on a gnat's bum compared to everything else.
It should be noted that the MOST fuel consumed/wasted is not by the cars themselves, but by the spectators attending the race. Even spectators attending football use fuel even though the sport itself doesn't.
We all know that and it's completely irrelevant for what we are discussing. Mind you, I don't say it's wrong, I say it's irrelevant.
Formula 1 is a high profile useless activity: the perfect target for a campaign to get notoriety and pass a message. Yeah, a transatlantic flight uses more petrol than all twenty cars in a race, but you can't stop transatlantic flights and you can stop motor racing altogether and the world wouldn't notice. It's not a question of number of kilograms of petrol used, it's a question of notoriety, image and marketing. It's not quantitative, it's qualitative. Formula 1 is a symbol.