Consent
Interesting piece on consent but it falls foul of EU laws on processing personal information. Because they will know where you are based on the data hoovered up, any advertising served that is "local" to you is using geolocation and the law prohibits that without explicit consent and a user must be able to revoke that consent at any time without charge or loss of service. Making it a condition of taking a service is not explicit nor is it freely given. Of course being American they won't give a damn.
As for the parental agreement bit - that's no different from a website asking the child to make sure their guardian is OK with it or a phone in saying that they must have the bill payer's permission to use the phone. Not exactly the hardest bar to clear!