I didn’t realise that the Rialto Bridge has a moving walkway and muzak, that the gondolas beneath it float on a clear blue pool, and that the school of Tiepolo had so many apprentices available to paint hotel ceilings. ‘Still in Venice, Martin?’ you’re thinking. ‘Surely that was last month?’ Well no, your intrepid columnist has moved from the old world to the new, and reports this week from the desert frontier where unfettered capitalism meets the lowest human urges: Las Vegas.