Thanks for pointing it out. Would've been great to have URL to it - as I just checked again, and it's not there. Other mods also do not see it.
As you noticed, post is a Sponsored post. Sponsors pay for advertising, keeps site going. We think, it was an ad post generated by TN site.
Hope this helps. Likely, some glitch on that process placed them in wrong forums, then Matrix reloaded, and they are gone.
In regard to the OP's original question, don't forget that Toyota Nation is just one forum in the scores of forums owned in Autoguide's forum portfolio, and so there are vendors and/or advertisers who can and do choose to cross-post advertise between forums. So if you see that kind of content, you'll know why. You may not agree that the advertising should be in a particular forum, but, hey, it's advertising. :dunno:
I had been in a discussion and was vehicle/model specific in which the details I had put in my signature would clarify a lot. As I don't repeat this in the post. I run in DARK mode and to my amazement. The hidden signature once clicked on to show it (should be visible by default not hidden) was...