Or do they spread something just to bet something different?
What do you mean?
I don't see any advantage to spread something like that. Even they do sports betting, it won't increase the chance to win the bet. The win in the match isn't influenced much by the news.
If you were a sports journalist, would you enjoy betting on the sports you report on?
I will always bet on the sports that I assume to have a higher chance to win it. I don't care whether I report the news of certain sports, I will prefer on the possibility of the winning chance. I'm not a typical of bettors who prefer betting on their favorite teams.