As I started this thread a few months ago I thought I would chip in.
After a lot of pressure 3 guys from Virgin turned up and removed the redundant cables. Like you I didn't see why a number of other users should be cabled to the box on my house, and even transiting the garden and just passing through.
There was no wayleave either sort or signed by me the owner or my dad or grandad, lets put that one to bed first. Unilateral action by Virgin Media was the key here, no permission. Lets also put the Telecommunications act to bed also. Without either a request for, or issuing of, any wayleave was sought by Virgin, and respective issuing would keep them on their toes for years. You could grant them a wayleave if you wished, at a price, they cant under the terms of their Telecommunications Licence just turn up and work on your property without your expressed permission. It all revolves about permissions which have been ignored by Virgin. and if they attempt to wave the Telecoms Act under your nose, you may wish to remind Virgin, that with the Act also came responsibilities which they have ignored.
No, the Telecoms Act although useful to Licenced Operators, also carries with it Responsibilities which have been blatantly neglected to advise you of.
Virgin actually nailed the cables to the wall of "my house" a definite nono.
So you have two issues, how naffed off and how many users will you allow before you take action and secondly, when all the Virgin users have left the area who is left with the bill to remove Virgins property from your house and garden.
Whatever you do, no matter how tempting it may seem, do not cut the cables yourself, somebody may be using the connection for "lifeline" or some other similar service.
This "board" is a good place to register your complaint first of all, Virgin does monitor it to help sort problems, and keep coming back to the board weekly until some action is taken. You can clways rent Virgin space on your wall is they wish to continue to use it, and also rent them space.
.You also need an undertaking from Virgin they will remove the cables at end of life of the cables at their own cost.
Make sure its well documented especially on this board.