You shouldn't have to be told not to block off Churches and roads with barbed wire, or not to graze and water your cattle on another cattleman's land in a drought without asking the landowner permission.

Part of the issue is that those social norms weren't established, at that point. The open range system pretty much required random folk to put up fences across most every road (cattle grids weren't common until the 1920s), and there were actually pretty big incentives to build and maintain property on public federal land. Property and trespassing concepts get very complex even today in that part of the country, and before the Fence Wars they were even less settled. In some places, ranchers and fence-cutters were able to actually meet up and agree on new rules similar to the norms you've described.

But more often, the conflict was more fundamental. Much of the fighting occurred where ranchers were not blocking off public roads. The cowboys and their employers had spent decades with access to these water supplies and grazing lands, and had their livelihoods dependent on that remaining the case. The ranchers, meanwhile, were spending years of their time trying to establish and develop portions of land, under circumstances that encouraged them to select the very water supplies cowboys valued and use as much of those resources as possible. And the economics of the time encourage both groups to nearly or completely overgraze land.

There aren't always easy solutions.