Earlier quoted context omitted.
They will have to buy it from some other company then: if they don't have the bandwith, they shouldn't sell it.
Not only that, but more users for them means more money to buy hardware and upstream bandwidth and hopefully some profit. That's the reason people are paying them. Perhaps telecom is different than most markets, but more users generally drives costs down, not up.
Then, to buy from somebody else you have to presuppose some open, free market with excess bandwidth. That doesn't exist today.