For most people it's not worth the agony of booking say five one-night stays instead of one five night stay. But, as others have pointed out, it sometimes saves some money. (Other times it might cost some money.) . But another possible advantage to serial bookings is that, since free upgrades are contingent - among other things - on the upgraded room being available for your entire stay, you improve your odds for an upgrade with shorter stays. And, if you don't make yourself obnoxious in the process, the chance to discuss your unorthodox booking at check- allows you an easy way to request upgrades for any nights they are available.