Every Paris itinerary comes with the same greatest hits: the Eiffel Tower, a walk along the Seine, and more croissants and wine than you can reasonably justify. Although that sounds like a perfect vacation, if you want to understand the city rather than just photograph it, spend a morning in one of its markets. Wandering through them is as much a cultural education as a few hours in the Louvre or a deep dive through Versailles. And, you…