I don't understand you. You're saying we can go about, say, murdering people and we are fine with that as long as we don't get caught? Is breaking social agreement acceptable if enforcement fails? If my personal ethics allows me to break the law, but enforcement fails, can I still claim to be a positive element of the society?

What I am saying is that society has agreed not to damage each other's property, has agreed to a certain principle. The society has, basically, agreed that enduring outdoor ads is acceptable, while enduring random property damage is not, as there are no exceptions for ad vandalism -- that's what I call to respect here -- agreed principles. If we don't agree with that, we must change the law. If society we live in is ripe for the change, then it should be possible. If not, we have no moral right to do property damage while leveraging all the benefits of living in that society.