When you enter a shop you become a customer, not a human being with feelings.
Same goes for those platforms. You enter it and you become a consumer.
If you're like it or not.
We're talking here about the right to get a copy of your own data, the right to be forgotten when you want to leave, the right to be informed about data breaches, and a right to agree to types of data processing.
Your analogy is "you enter a shop and cannot leave again, may be abused, and lose control."
Neither is google