A privacy policy sets expectation which can be compared against. If they promise to not sell your data, then do, you can do something about it. If you read thi

A privacy policy sets expectation which can be compared against. If they promise to not sell your data, then do, you can do something about it. If you read this, you owe me 10 dollars. So this is the email disclaimer argument. Email disclaimers are admittedly useless, but unless they stop being common-place, they will become accepted.