There will always be exceptions to every or any type of rules regarding such decisions. However, that said as a disclaimer, I think that most times the situation is obvious. For those exceptions perhaps a board of inquiry is in order?

Larry brings up a good point that I didn't consider. Insurance. If a knucklehead requires a rescue and turns it into his/her insurance, that will ultimately punish the rest of us through higher premiums. A personal "invoice for rescue" where the individual must pay out of pocket for their stupidity would have more impact and perhaps would cause second thoughts on committing said act? Actually, I'm not sure what you can turn into your insurance company other than a claim for the boat and personal property?