As mentioned earlier, the Senate's atmosphere may not appeal to everyone. While there are similarities between the two forums, the topics are approached differently. Kavar is primarily meant to be a friendly place to discuss current events and other "serious" topics with a lighter tone ( and often less rigorously ) than in the senate. I think both forums have their place here.
Besides, there is also a different community feeling that has been created, even if several people who post in one forum also post in the other. Every LF board has a general discussion forum, several of them have RP, etc. I don't see why we should be restricted to only one "serious discussion" forum