[blackoil]

Isn't that how the TRP is calculated. IIRC agencies install devices in random houses to find which program is being watched.

[Nextgrid]

The difference is that this is done with the user’s explicit consent and I’m pretty sure they get compensated for it.

[drevil-v2]

Sample of houses IIRC 10,000 in USA. That's vastly different to installing the device in every house in America.