Who is Watching?

As the ATM was processing my withdrawal and preparing to hand over some cash to me, the screen displayed something along the lines of "Who is Watching?". Presumably this was to encourage me to be aware of people looking over my shoulder trying to grab my PIN. Or perhaps inviting me to be wary of someone watching me from a strategic location, ready to pounce on me and relieve me of my grocery money. There is a small mirror fitted to the ATM, ostensibly to aid customers in spotting who is watching.

I'm not sure about the machine I was using, but many ATMs are fitted with cameras to help banks do their watching. And many street corners in the Sydney city now feature loud-speakers attached to the traffic lights in the name of allowing the authorities to broadcast instructions in the case of an terrorist attack - presumably there are cameras involved too. I wonder if perhaps the ATM was inviting me to think about who is watching me at a slightly deeper level.