networkn: I was horrified to find out that at home, a dialtone via pstn costs a whopping $50 a month! I was pretty gobsmacked by that! Though I am still at a loss to understand how naked dsl costs more than standard DSL.
Ya, it's normally less than POTS and DSL though.
The copper maintenance costs are currently mostly on the POTS services. When you get DSL over POTS, you only pay a very small portion of the cost of servicing the copper because the line share is apparently picked up by the POTS provider.
So, when you remove the POTS, the copper service fees get handed to the DSL provider...
...at least that's the story we've all been living with for a decade. ;)