This has taken place in Australia, COVID-thread police.
Met up with two other labrador owners and took our three labs to the park. The park is enormous with a very large pond in the middle. Half of the park is a fenced off-leash dog area with the pond forming part of one boundary. The other half of the park is an on-leash dog area. The pond is enormous so dogs swimming on the off-leash side never seem to swim over to the on-leash side.
The labradors were playing fetch in the pond from the off-leash side when a man launched his remote control model yacht from the bank of the pond from the on-leash side. He sailed his yacht right past our labradors in the water who were playing fetch. About 2 metres away from then. Two of the labradors ( not mine fortunately) grabbed the yacht and had a game of tug-of-war in which the yacht sails were torn and it got scratched and battered about.
The yacht owner was furious and wants my friends to pay for the replacement of his “bespoke sails” and general scratch and dent repairs.
YABU- Owners should have complete control of their dogs at all time, even in an off-leash area, and if you are not confident that your dog will leave an item in the water, even in the middle of a game of fetch in the water, you should not have them off leash
YANBU- Yacht man was a complete idiot and no one with half a brain would sail an expensive model yacht right past excited labradors playing fetch in the water.
I personally think yacht man was a complete fool but I would expect my friends are legally responsible for repairing the yacht as their dogs damaged it in a public place. They don’t think they are, so it will be interesting to see if yacht man takes it further.