I think this is an example of contracts being broken, often online but elsewhere too. You can't rent a hotel room without a credit card which helps hotels avoid you running off without paying for minibar peanuts or rock star damage to a room. OTOH, the fact that you can't update your iphone, rent a hotel room or do a lot of other things without agreeing to a "contract" or policy so long that it's impractical to read…
On the note of bullshit contracts... We are about to shell out ~£15k to a recruiter who sent us the CV of someone (completely cold, without the person's consent, or us having any relationship with them) we hired via another recruiter, but a year down the line are pressing a claim, as in their contract, receiving an email from them is deemed acceptance. This is apparently perfectly legal in the UK, and I'm considering…
Probably not enforceable -- but it'd be hilarious if having a no-bad-review clause in your T&C made you liable to, for example, the Flappy Bird developer.