BT wants to steal bandwidth - again!

Yet again BT is flogging its FON servicve to customers without warning them that they lose part of their bandwidth. FON dellivers free access to mobile users via existing BT subscribers with wi-fi routers across the country and is a very good idea BUT. The but is that if you have 8meg giving up 200k is flea bite. But out here in carrot land we get 400k if we are lucky. Handing back to BT up to 200k strikes me as a bad deal. Worse the ad that drops through as UCE (Spam) does not make this clear. Seems to me misleading at the very least.