For at least one cruise line some folks from CruiseCritic got together on line and did a series of test searches. They made sure everybody was looking at the same ship, sailing, and room category. They tried signing in with and without their loyalty program number, they cleared caches, they made sure they were looking at full cost including tax and fees, they were from a number of states from close to the embarkation port to distant, and so on. The variation in the price was actually quite surprising. The biggest surprise, and also disappointment, was despite supposedly there being a reduction or discount for being a returning or loyal line passenger the posted fare was often at the same cost as a new passenger could get and even sometimes higher. The end result for me was I was even more convinced to stick with my Internet agency/agent and get my 10-12% discount from them.