Castnetting is legal everywhere in public with the rare exception where it is posted that you can NOT net, such as below many dams for example. I been doing that to sustain my catfishing habit for the last 10+ years, LOL
Now we often run into similar situations and we always ask if people mind if we throw and yes, I understand the banging of the nets on the dock, its kind of how you do it, no way to get around that and I can tell you the fish generally are used to dock noises because Ive castnetted it all, bass, stripers, walleyes, about every species in Ohio and often from a dock.
At CJB the serious guys are smart enough to not castnet in the marina from shore because of the structures, Ive lost two nets there this year already so we usually only castnet the marina when Im in a boat and can get most of the snags back by dragging in the cedars if need be.
Not saying they were right or wrong without being there but most guys try to work around fishing folks with some courtesy but at the same time Ive had folks go off on me for spooking the fish when I was well over a 100 ft from them...
Salmonid