Legal Contortionism

"This unlimited Bolt On is for customers who only want to browse the internet and send emails and is subject to a fair usage policy which operates above 200Mb usage per month, or approx 1,400 internet pages per month."

I challenge anyone to tell me why that is a fair way to describe what is essentially a 200Mb data tariff bundle... I cannot contest that O2 are being very generous here for £7.50/month, far more generous than their peers with 30Mb caps and the like, I just despise the way all the operators can claim "Unlimited" bundles which have explicit contractual limitations in them.