I suspect it's because British commuters travel further in general than mainland European ones, and public transport costs are higher. It's hard to park anywhere now in British cities too unless it's provided by the employer.
That's certainly an element, but I see the same type of grim faced, helmeted and specially clothed, fast riding among those who have shorter commutes in London. Seeing bunches of them racing along together has all the appearance of a peleton, regardless of their trip distance.
I remember when young and in the days when most of Britain cycled, my father cycling between East Bedfont and Charing Cross each day, not a short distance. Like virtually all others then, he sat upright on a utility bike, cycling at the usual circa 12 mph or less, so no different than those European cycling countries now.
The difference is that they never stopped utility cycling, we did, leaving only the residual sporting model for the future to model itself on.
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