I wouldn't say it ruins fishing spots but I do think it makes anglers lazy , instead of jumping in your vehicle and checking things out they just go to the net , even when it comes to smelts you see questions on here all the time. Drive down to the river and see for yourself same with steelhead. Before the net we got in the truck packed our gear and went to whitefish lac or where ever . Although the net is a great learning tool on tackle & tactics again get out and figure it out on your own.