They barely consider the other benefits they gain. SEO, direct advertising they are getting, or whatever else. In most cases, only the stats from the tracking URL matter. Well, it's not that bad either for most campaigns if they put effort into solving issues here, increasing engagement. I don't want to share stats or name, I have seen a decent amount of GGR from campaigns I managed.
Exactly. There are more benefits than just the right clicks.
Also, they can hardly look only at the source of the traffic, knowing if a forum user doesn't visit them without clicking on the link.
In fact, they should do a more comprehensive analysis of the benefits of having a forum campaign.
I believe that campaign managers try to convey this idea, but I also know that sometimes this is not easy.