There is no reason for an 'a la carte' system to be cheaper. Actually transmitting channels is basically free. So, assuming there is 250 channels, and everyone

There is no reason for an 'a la carte' system to be cheaper. Actually transmitting channels is basically free. So, assuming there is 250 channels, and everyone watches 5, but a different 5, it costs the same to let everyone watch all 250, or exactly 5 of them.