VTWC pay track access charges just like everyone else.If Virgin Trains had single handedly built the West Coast Main Line, and bought their own trains to run on it that might make charging this much a bit more palatable.
I think you'll find that is because people are willing to pay more to go from Manchester to London than they are from Berwick-upon-Tweed. VTWC, VTEC, BA, National Express, etc. are businesses that exist to make money for their owners. There is no reason for them to charge less than the market will support.Unfortunately railways are important for things like economic growth, and transport should be viewed more as a service than a business. That's why it's ludicrous that an Anytime Return from Berwick-upon-Tweed to London is so much cheaper than one from Manchester.