I remember briefly seeing a Direct TV or such commercial with the announcer saying something like 'look, no one can give you cable a la carte...' Well, why not? That would be so much easier. I'd keep a lot more cable if I wasn't paying for dozens of channels I don't watch.
Because that's the only thing that can keep the smaller cable channels existant. The draw of the larger channels - HBO, Showtime, ESPN, Comedy Central - subsidizes the smaller channels, and with cable a la carte the smaller channels literally wouldn't be able to exist, because while they have fans, they don't have enough
fans to survive based just on the ones that would choose to subscribe to them. You'd be limited to only the current biggest cable channels. Food Network, Syfy, Discovery, AMC, pretty much any special interest channel would be dead under an a la carte system.