because none of them can and none of them have a financial interest to do so. Default free providers such at NTT, GTT, Zayo/AboveNet, Level3/Global Crossing, A

because none of them can and none of them have a financial interest to do so. Default free providers such at NTT, GTT, Zayo/AboveNet, Level3/Global Crossing, ATT, CenturyLink/Qwest, Deutsche Telekom, Vodafone/Cable & Wireless, and others commonly (but incorrectly) known as Tier 1/"backbone" providers peer with other networks in a settlement free (no money is exchanged, or, on an accounting basis, everything zeros out) fashion because they are "peers" in the strictest sense: same size, same reach, same markets (mostly...) there is no danger for them in passing bits