Because that's how things work in a lot of other services? For instance, if you sign up for shared hosting and go over your alloted bandwidth, they may charge

Because that's how things work in a lot of other services? For instance, if you sign up for shared hosting and go over your alloted bandwidth, they may charge you $0.50 a gigabyte or so. That is linear and it seems reasonable. What would happen if you could stream high-quality video from mobile phones? With large data transfer capabilities would come interesting new possibilities for markets, companjies, and customers.