[omginternets]

You have to show yourself, and this increases the chance of people reporting a strange man taking photos of a house.

Yes, it's not cryptographic-level security, but it raises the costs of an attack. In the real world, that matters.

Also consider that not all attacks are spy-vs-spy. This could be a case of 'keeping honest people honest', i.e.: making it sufficiently difficult to dissuade the majority of political activists and/or protesters. This is the same reason why padlocks are a thing.

[viraptor]

> You have to show yourself, and this increases the chance of people reporting a strange man taking photos of a house.

In the year of pokemon go players everywhere? And even then, who cares about a person with a mobile phone? We're a good decade after anyone is a "strange man" when taking photos anywhere. You don't even have to show yourself. Just order a cab and go through that street without stopping.

> dissuade the majority of political activists and/or protesters

I'm not convinced. The only thing the blurring did was prove that this is the interesting house, rather than a name coincidence. What is that supposed to dissuade me from if I was already going to go there and do something potentially illegal?

[omginternets]

It may or may not be effective, but I think this is the underlying principle.