The thing about this is that it is wholesale internet. I'll use my ISP TekSavvy as an example. They offer 512kbit/s (which no one uses) as well as 5mbit/s DSL internet from which the transport is provided to the customer by Bell. So TekSavvy has their own routers and pays for the bandwidth from Peer1, Cogent, etc.
As of right now, they offer 200GB of bandwidth with a 5mbit/s connection for $29.99 and a dry loop fee if you don't have a copper phone line. That's quite a bit of bandwidth and the overage fee is only $0.25/GB. They also offer unlimited bandwidth for $40, in fact nearly all Bell DSL wholesale providers provide unlimited bandwidth for up to $40. Most of the wholesale providers have razor thin profit margins because they keep prices so low.
What Bell is trying to do is charge the wholesale ISPs for the customer going over "Bell's" 60GB bandwidth cap. Bell does NOT pay for the bandwidth. So rather than have 200GB for $30, you'd need to pay approximately $52.50 for 80-300GB of bandwidth. Speaking of 300GB, there's another cap. Bell wants to charge $0.75/GB after 300GB, so that would probably be added on after the $22.50 max overcharge limit. Bell also claims that they'll send a warning for using more than 300GB of bandwidth and if you get enough warnings, they'll cut your service.
I could go on for a bit longer, but I don't want this post to get too long. The info is in that thread that I linked to from the TekSavvy forum, but if anyone really wants me to, I can summarize it here.
EDIT: Funnily enough, there's a Google Adsense ad at the bottom of the page for Acanac who provides unlimited bandwidth.
EDIT2: Heh. I forgot adsense works by showing ads for what you're already looking at.
