I have some insight into this... (but a contract signed a few years back means I can't mention "names")
Aussie free to air stations have a legal requirement to broadcast a certain % of Australian produced content per week, month, year.
4wd person, goes to them and says "I'll deliver you a professionally produced and edited show for FREE, I just need your guarantee that it will be shown in certain (reasonably) popular timeslots"
TV station says, "sure... show me your trailer/teaser for the show"
4wd person, then approaches 4wd manufacturers, parts importers, trailer manufacturers and so on and asks them for cash (and product) sponsorship, using the agreement that he has with TV station to promise a number of potential viewers for the show.
So basically... the 4wd person needs the sponsors money to finance the production of the show. But that only works if the TV station guarantees to air the show in a reasonable timeslot for the sponsors to get their perceived value from it.
it's all a juggling act. But the end result of this is... no sponsors... no show.
And to be clear... I don't the like the endless infomercials throughout the shows either. Shits me to tears.
My personal gripe right now is each of the 4wd/camping/travel shows having their own sponsor for camper trailers and so each of them promotes the begeezus out of that brand. Apparently their brand can do no wrong. (which is total bullShit and we all know that)
*grumble winge grumble*