polygonum wrote

Because BT make most of their profit on calls, therefore they want
you to
make some. They want to discourage you from having a line you only
use to

Can see what you mean if it is a vanilla line. But if the tariff is
one
where the calls are not charged... ?

If no calls are charged, true. But there are still mobile, special 08xx
and international calls not included in such add-ons.

--
Mike D