> How much can you sell it for? Really - let's say you have my entire viewing history for a year, let's say I'm from a valuable demographic, how much would that be worth? A dollar? 10 dollars?
It isn't just what you watch. It means they know when you're home and when you leave. By watching what you're watching they can make guesses as to your race, sex, income, politics, marital status, how old your children are, what your interests are, etc. Not all of that will be 100% accurate, but they don't care. It just has to be accurate enough that companies who buy the data will see an improvement in whatever their aims are. There's no PR backlash to worry about because you aren't allowed to know who they sell your data to, or how much they make off of it.