That's frightening. But I'm glad to see that at least in the US, the ACLU have already identified the problem and will likely be taking steps if it becomes an issue. In the US, the right to privacy still holds.

Organizations like the ACLU and the Electronic Privacy Information Center have been way out ahead of this new way of watching. The former has written an ethical framework for facial recognition, while the latter delinated very similar concerns in a 2014 letter to the Department of Commerce.

It will probably only take one well-placed lawsuit against a corporation doing this to make it a less profitable way of advertising.