The problem is -- this is the standard and universal method of adding a banner to nearly every forum in existence. They're all like this.
Also, this is something you would have to take up with the Kunena team. They're the ones that implement all the coding. Kunena is essentially a forum extension that Joomla (the webhost) uses for forum construction. Joaquin only has control over the game of Dogfight and other Echoboom Apps.
Here's the Kunena website if you'd like to make such a suggestion:
www.kunena.org/