Why is it that even a simple survey question about boating pollution is somehow a threat to boaters? Boaters pollute, it's undeniable. We should be interested in reducing that pollution, not in justifying it.
The fact is, that there is not one single thing people do that doesn't pollute, or effect the earth in one way or another.
A single factory produces far more waste and pollution than a couple hundred boats on the water. Oil leaks, from the trucks/vans/cars/trains/ships etc used to ship products pollute far more than all the recreational boats in the US, all of it eventually ends up in the waterways. Insecticides used on nearly every farm/lawn in the US is not really controlled (Oh you do need a license to spray some, but no limit on how often or where it can be used) All of it ends up in the water system. But, what did they target? bottom paint.
The problem with a bent survey like this is that some political group or even lone politician will end up passing a 'feel good' law to show what they are doing to clean up the environment. Ultimately, the law will have no effect on the overall water quality, but they will be able to point to it and say " see, I care, look what I did", of course the only group it will be aimed at is the recreational boater. Factories and shipping companies will be able to buy oil credits, will be grandfathered in like most city sewage systems, or exempt altogether for some reason or other.