It's sad that the peelers got involved in this. What's the problem if the bloke was running an electric boat? A club I was a member of used to get hot under the collar if non-members used "their water" (not that it bothered me). Yet anybody could use the pond during the permitted times and days.
We were at another park lake once on a day and time when boats were permitted, run by anyone ... not just club members. A bloke who was there with two young lads catching tiddlers in little fishing nets went whinging to the park attendants. They turned up in due course and gave us a lecture about noise, pollution,etc as expected. We explained that, according to the park rules, anyone could run boats (even I.C. which we were running) on that day and at that time of day. Again the parkie repeated his lecture. Listening to him and "reading between the lines" I got the impression that he was thinking "Yeah, I know what you're saying and we know the rules, but this bloke is a whinging **** and we all could do with a quiet life so ....."
So we packed up and left, leaving the whinging tiddler-catcher smirking all over his face. Well done to him, ******!
So, there you have it, even when you abide by the rules and regulations, if somebody complains you can still be in the wrong.