Sean is absolutely correct. Whatever you use your land for you should have the right to enjoy it peacefully without golf balls landing on your head. What's more that's the legal view so the ridiculous position would be to ignore the law.
The other thing to maybe consider is that when this hole was built and the caravan park was built, it might not have been in range from the tee anyway so perhaps it wasn't a consideration ? Whatever the truth in that suggestion, their has been concern about this hole for decades. I first played the course when it was the old hole (25-30 years ago ?) and it was straighter and less left to right. I only have a very vague memory of it but the mound to the right, which I think has been reshaped to shift it right, was less pronounced and bang in the middle of the fairway such that the ball would tend to slip off either side.
The initial change was to make it a left to right dogleg. They subsequently brought the OB in so that balls landing hard on the mound could easily get a hard kick OB. Members were well aware of that and tended to play left side of fairway.
Re proposed new 10th. It was never a great hole but it was a tricky one. For as long as I was a member their was talk of buying the field beyond to extend the hole and I vaguely recall that was Dr MacK's thoughts back in the day also. That talk seemed to go away once they rebuilt the current green in the early 2000's. There was also the suggestion then of putting a tee in on the first dune ridge to the right and rear of the 9th green. It would have made the 10th a straighter and better hole but also a much more dangerous one. At the moment it's a sharp dog-leg left with OB (public footpath) beyond the landing area for the drive. In all my time as a member down there I never saw anyone go OB That wouldn't be the case with the new tee hence presumably the idea to move the green ?
The only problem with moving the green is it's my understanding their is an old Roman fort up in that area to the left of the dog-left of the fairway which presumably they would need to circumvent ? It all seems like a lot of work to resolve any issues with the 11th.