But imposing your own preferred art on public commons is a (minor) form of violence, in any economic system. Especially when you do so with paints of questionable chemical composition, or with images/text that is likely to offend.

I would also say that doing the same thing even on your own property can be reprehensible, as long as it is visible to the public. Just because you own a house doesn't mean you should be able to make it look however you want on the outside, especially not in ways that are actively unpleasant to those of us that need to walk by it every day: we the public should have a say in how your private property looks. A most anti-capitalist position.