Far too many SAR aircraft are scrambled due to people essentially not taking proper precautions, and being prepared with respect to basic safety, and this is not just applicable to flying. This is an unnecessary cost both in monetary terms and in terms of the safety of crews who are going to come out and try and find the hapless individuals, who are expecting a pick-up when all goes wrong.
i don't see how that is totally relevant to the argument. If an aircraft does goes down in the water, SAR would attend whether the aircraft had floats or not; because the occupants would still need rescuing.