Somehow it's perceived as a norm that you can't arrive at work, a restaurant, or the store, with any amount of sweat on you. There's a bit more to it than this, of course. Most American cities have more extreme climate, longer commutes, and more hills, than in the northern European cities that are held up as the gold standard of cycling culture, but people ride bikes in southern Europe too.

In turn, this makes it "necessary" to wear special cycling garb, change, and shower when you arrive at work. Vanishingly few workplaces provide a convenient place to shower and change.

But I ride my bike to work year-round in a city that gets (for instance) about 10 degrees hotter than Amsterdam, and I manage it.