You can block users.

No harm was done to the stonehenge. No harm was done to the cause to stop climatechange. These actions get people talking about climate change, that is the plan and it was a succes. There are many different types of action that can be taken. Some people write letters, other consume less, etc. In the end they all work towards the same goal. But they require action. If you are not interested in changing the world and yourself for the better, no one can convince you. But if you want to create change, you will and you can. And then you will do so no matter what other people may think or do.

If you support the cause you would understand no harm was done, and media attention was generated, as planned. If you want to have a excuse for your inaction you bitch on the internet about it.