Very much this. In fact I would suspect the extreme opposite is performed, by anorexic hyper miling people looking at the wind directions for any possible advantage - the brake pedal never to be touched.

I took my old (APR ECUd, rear sway bars, otherwise stock) turbo charged Polo GTI on the Winston racetrack once (V8 trucks practice day) to work on my driving skills, and it was surprising - but not at all unreasonable - to see the remaining fuel in KMs estimate perform a complete nosedive.

The fuel efficiency numbers of the F1s are truly awesome.

Exactly. Take any car and race it flat out for two hours; see how much fuel you burn. Especially with a turbocharged car, it's possible to have pretty decent fuel economy in regular driving, while still going through a ton when you're really pushing it (and getting the power to match).