Is it frustrating to have a trip cancelled, whether it's due to waves or economic contingencies? Of course, but that's part of the game going in, so it pays to make appropriate alternate plans when possible.
With all due respect, no it isn't. The possibilities of weather cancellation is certainly part of the game and there are mentions on their website about this possibility and how it will be handled. Show me anything on their site that warns that the trip won't go if they get a better offer. When someone asks for my business and I give it to them, I expect a little appreciation. Canceling out on the deal they had with me to do business with someone else makes me feel anything but appreciated.