Parisiens buy an extra baguette on the last day in April. They know the town will shut down on May 1. The occasion is Workers Day, the Fête du Travail. Neighborhood cafes are packed with families enjoying a meal and the warm weather. Every second person carries a lily of-the-valley nosegay. These are sold on street corners by aid agencies. Paris waives the sales tax this one day. It's a sign spring has arrived.