gl556tr...perhaps I haven't made myself clear.
BT spends a small fortune each year, fixing problems with underground and overhead cables. Every time we have a storm, telephone cables are dislodged or blown down. The underground cable network is also easily damaged, by flooding, road works, etc. So a charge for the rental of the line must be made, in order to fund these costly repairs.
The same problems face the supply of gas, water and electricity. If there is anything else you don't understand, please feel free to ask !