We don't. We just relocate slightly upstream and now they have to drink our shit!

It's been awhile since I read this so I'm going to mess up the details so I apologize. But I believe it was in the book Debt the first 5000 years that David Graeber shares a story from an African tribe that he had an account of.

In this tribe it was custom that if someone remarked on something or asked for something that the people of the village were obligated to give it to the asker. And there was a man in this tribe who every day would go to the fisher and comment on the best fish they had caught so if course the fisherman were obligated to give it to him. And then he'd visit the weavers and comment on the best basket they had. And so on and so forth up and down the coast he would do this and everyone knew who he was and that he would do this and the merchants got upset and got together to decide what to do. Custom says they cannot refuse him when he asks so they concluded that there was only one logical and egalitarian thing left to do. And so they formed a mob and killed the guy.

So what do you do if someone is shitting up stream and won't stop? First you try talking to them. If that doesn't work then you get your union to talk to their federation to pressure them into cooperating. And if all else fails then we fight to protect our health and our way of life. Anarchism isn't pacifism. We can protect ourselves from those who will destroy our way of life and oppress others.