What are kids –young people, 15-year olds– wearing in Paris these days? someone asked me.

The obvious answer: sportswear. Two brands hold particular sway: Abercrombie & Fitch, and American Apparel.

In their native America, both brands have developed a reputation with risque advertising.

Abercrombie & Fitch is partial to black-and-white shots of groups of shirtless, hairless, young men; to me, they look like a riff off Bruce Weber's work for Calvin Klein a few decades ago.

American Apparel doesn't have a single look or theme, but it likes seemingly impromptu, Polaroid-style moments with young women, often on a on a couch or rumpled bed. The photographer seems to take a prurient interest in the model, to which the model seems oblivious; the photographer is letting us in on a dirty joke.

In their campaigns, both brands share this: they court controversy, and they seem calculated to inflame a raw nerve with parents.

But here's what amazes me: neither company advertises in France (or, if they do, the advertising is quiet and confidential), and young French shoppers are unaware and unsuspecting of the brand's sultry reputation in the US.

In France, Abercrombie & Fitch is popular much as Levi's jeans were in the days of the Soviet Union. They're imported from the US (or from a lone European outpost in London), and they send a message more subtle than an "I [heart] New York" (or an Obama "Hope") t-shirt. The apparel otherwise seems in sync with comfortable, egalitarian apparel that young people favor.

American Apparel takes the egalitarianism a step further. There's no brand. But it's identifiable from thirty paces. What makes the line distinctive, what sets it apart, are color selection and, to a lesser extent, how garments are cut. I've often walked past its Paris store, which is low-key, even boring-looking.

How did either of these brands take root among young Parisians? It's a mystery to me.