I had that happen on my home lake ( that I had been fishing for 35 years or so at the time ) I had taken a friends teenage son fishing and we had found a dock holding some nice bream.
We had caught several nice bream when the owner came out and told us to leave. He said with an attitude that his grandkids fish there and he had a problem with us fishing there.
At first I was completely shocked, then it turned to intense anger. I knew that if I said what I was thinking and feeling It would get much, much worse. Having my friends son there and being a man of faith I just left. If that had happenned when I was younger it would not have ended well. I was not sure I could handle much more of it, so I left , and him still running his mouth. I had every right to be there, had been on the lake much longer than him, was not touching his dock or otherwise acting the fool and still got his mouth and attitude. I thought, I have grandkids fishing at my dock too, and it wouldnt bother me if someone came up and fished as long as they werent out there.
Grevious words stir up anger. Knowing myself, and how I can be , I just left before it got worse.