Happened to me last week. Went bank fishing at the river. This part has 3 islands. I set up all my gear and got one line out. On an island with no one on it.(Catfish/Gar fishing) Turned around to grab my 2nd rod to cast out. Some guy waded from another island and stood 2ft from my first rod and started casting. Mind you there was 2 other islands empty.
I guess I wasn't in the mood to deal with it. I said to him " your kidding right?" he just looked at me and didn't say a word. So I grabbed my casting net and started throwing everywhere, Even right in front of him. Didn't stop him. So I grabbed one of my bass rods and as soon as he casted. I casted and snag his line. Just played dumb and said sorry. I did that 2 more times. back to back. He finally got the message and left. I normally don't care at all. Specially if they ask if they can work in and fish as well. I've never told anyone No when they've asked. I've meet some good people that way fishing. I've never been that rude to anyone out fishing. In my job I've learned to talk my way through some tough/heated moments with some of the roughest characters in sketchy moments. ( to say the least)