THE $12.2 billion deal in which Marriott, an American hotelier, will buy a rival, Starwood, follows months of rumours about the bid target, whose brands include Westin and Sheraton. In April Starwood’s slow growth, at a time when other chains are doing well, prompted it to start exploring “strategic and financial alternatives”. Marriott’s acquisition, announced on November 16th, will make it the world’s biggest hotelier: it will manage more than one million rooms, about 50% more than its closest rival, Hilton.The deal comes at a heady time for hotels. Eight years ago Blackstone, a private-equity firm, bought Hilton for $26...