A) "So it's UDP vs TCP" <- no... you should read up on "QoS"
B) "why can't" <- I did not claim they cannot... I stated that they don't (they don't even use the same frequencies in the air), and that even if they did, you wouldn't charge the same due to the QoS differences.
B) "why can't" <- I did not claim they cannot... I stated that they don't (they don't even use the same frequencies in the air), and that even if they did, you wouldn't charge the same due to the QoS differences.