Is it really? The amount of people willing (and able) to pay today 10-20 is likely ten times the people who paid 100-200 in previous generation. You see the same in gaming and film, where you have many many more consumers today than you had 30 years ago, and still they complain about “piracy is killing industry”, while their profits are through the roof.
It's also worth mentioning that these services are very big outside the US. Premium (cable) TV was never such a big thing in other countries, and those where it was somewhat popular never charged as much as the US.
