Makes a lot of sense. A TV channel is just a stream of data, so just stream all the data you might need over and over and over.
It's not even so much 2 way communication in the local cable system as the fact that cable TV companies were not originally ISPs. Sega Channel was a broadcast over C band no-return-path satellite, it didn't have any Internet related moving parts.
They would buy a 30 minute paid programming in the early hours on cable TV networks under the name "Teleworld Paid Programming". The box would tune the channel, record the show, and then decode the data from the recording.
I always thought there was something interesting there, as the process would need to survive the MPEG encode/decode process on the TiVo itself in addition to whatever they needed to do the broadcast.