Any TV coverage can only be a good thing. However small.
The fact is some may be watching who won't neccesarily be speedway fans, see it on the prog and say "Hey, I fancy seeing that" and go along to their nearest track.
As a certain supermarket says in their TV ad's "Every little helps."
Oh, and one other thing, it's basically a FREE advert, as speedway probably hasn't had to pay a penny for the exposure.