That's almost 250 GB a month. How do you use that much on a mobile device? That's more than most people use on their regular Internet connection.

Tethering. cough. You can do that with many non-thethering plans on some jailbroken devices to save money or get around no-tethering allowed companies. I'm not going to lie and say that more than 10% of that traffic accounts to youtube videos and torrented linux distributions...