Joe Biden — who recently had a one-night stay in Paris reported to cost a hefty $585,000.50 — treated some New York taxpayers to free dessert over the weekend. The veep and his wife, Jill, were spotted having brunch at B. Cafe on the Upper West Side, where they showed up somewhat spontaneously, while gobsmacked guests looked on. “Biden’s Secret Service detail called ahead and asked if they had ‘room for a VIP,’ without saying who it was,” a spy said. “Then Biden turned up with his wife and 15 Secret Service agents 20 minutes later.” The spy further related, “Biden shared his dessert with the diners sitting next to him because he was stuffed.” Dessert at brunch? What would Bloomberg say?