The Musée du Louvre. Seriously, you need to dedicate at least one full day here if you're into looking at old stuff that you'll probably never see anywhere else for the rest of your life.

You're just looking at one of the entrance areas. The Louvre is huge. Of course there's a shopping mall at one of the entrance/exits. In my opinion, Paris beats most major cities I've been to in the US when it comes to marketing & promotion. Animated billboards everywhere and store displays that are full tilt. Yes, the US has these promotion schemes, but not to this scale.

Some advice, get the Musem Pass (Carte Musee). The price varies depending on the number of days you want it for, but it's cheap, you can go again and again and you don't have to wait in line for tickets. (At the Louvre you have a special entrance)