I agree with the original post, inasmuch as that we should call the dive when not safe. However, your point is 100% valid. If you operate a business with thin margins as the charter boat business, having a policy that anyone can cancel anytime for any reason pretty much ensures that you go out of business fast. It is reasonable to have 24-48h no refund policy, and at that point the financial risk is on the diver. A situation where the boat tour operator takes 100% risk and divers take 0% risk (financial) is not where we are. It is possible, but then the prices would have to be 30-40% higher for everyone.
At the end of the day, diving is an expensive hobby and it is not in our interest to drive all boat tour operators out of business.
I am new to diving and when I started, following the advice of the local shop I got reg setup. After 9 mo, and 2 serious failures, I decided I do not want to dive with that crap anymore. They will repair it for free (1st stage crapped out after 16 dives) and now I have to buy another one and sell this (when repaired) at loss. It sucks, but what can I do. I am not going to dive with this crap anymore, as I do not feel safe. This is the same thing as calling the dive and losing money.