The problem for most ISPs, in the UK at least, is not the last mile but actually the last hundred miles. We have one Telecom monopoly: BT and one cable monopoly Virgin Media.

I agree with you that costs to Virgin Media should be quite low, as they own all of their infrastructure and most of it has been in place for 20 years or more.

The problem for the ADSL ISPs in the UK is BT. There are some IPSs which have installed their own equipment in BT's telephone exchanges and hence only pay BT for use of the 'last mile', but most of the ISPs in this country have to pay BT for not only the 'last mile', but also for the hundred or so miles before that. BT charges the ISPs based on how much bandwidth they consume, so for the majority of Internet users in the UK, the amount of bandwidth they consume is an important cost to their ISP.