Yesterday was a banner day for cruise tourism stocks Royal Caribbean (NYSE: RCL), Carnival Corporation (NYSE: CCL) (NYSE: CUK), and Norwegian Cruise Line Holdings (NYSE: NCLH), each of which sailed away with stock market gains -- boosted by Carnival's announcement of its "busiest booking week in the company's history." As CruiseHive points out, both "Norwegian Cruise Line and Carnival have already announced increased gratuity rates to combat inflation." Higher prices, even on such incidentals, can help to cover rising costs, and potentially even pad profit margins.