The reason for that is likely just because the content is from the Food Network, same as SBS Food Network currently.
No doubt 7 would’ve loved to have just called the channel 7Food but it’s probably a requirement of taking the content that the whole channel name is used along with the logo.
Which raises my next question, I wonder if V/O will say “on the 7food network” (which I think reads better) or just “on 7food network”? Semantics I know.
It might just take a few extra days to get the 7QLD multiplexes adjusted for the new channel. Even in metro areas, the service isn’t set up correctly yet.
There might be a video/audio stream currently allocated to 7Food Network here in Sydney, but there’s no content running so you aren’t missing out on much.