Just because channels are free to the customer does not make them free to the broadcaster. There is a cost involved with every platform they join. Virgin has the smallest "free" (TV M is not actually free, as you have to take a landline as well) audiance, & Virgins costs are higher as they operate their own network & boxes.
Cable customer since 1993. Services: FH TV, Sky Sports & Movies (2xV+), Talk Unlim Telco, VIVID 100, Virgin PAYG Mobile