In Chicago, it's considered acceptable, maybe borderline trendy to wear Asics to and from your downtown job. You switch into your work shoes once you get there. In Paris, I've never seen a pair of Asics on anyone not a tourist.
Here it's heels. Not necessarily high heels, but those too. It's wintertime, so boots for women. Men wear leather, brown or black, pointy. Man or woman, young or old, businessman or student, whatever you are wearing, it will certainly click.
No one talks during rush hour. Everyone is going their separate ways and rushing to catch the metro. So this sound, of hundreds of heels clicking on the lineleum corridors between metro lines, is a very loud one. And very Parisian.