Well that's just silly.. Lets think about it this way and please forgive my usage of names and analogies..
Lets say Mr. Jones doesnt have the DLC, but I would like to play with MR Jones, so I join his campaign as a home campaign, because well, we make a good PVP team.. if his campaign doesnt have the IC access at all, I can have to do without IC just to play with a friend of mine. there is nothing that says, that just because you dont own the DLC you cant go into an IC enabled campaign. Yes I know that most ppl are in the IC right now. it's new, shiny, and special. let the novelty wear off and people will go back to keep zerging, ganking on the roads and manning the Sej Bridge as a choke point. no need to have a campaign that just simply has IC disabled.. then what if Mr Jones decides to get his DLC access.. he has to pay outrageous amounts of AP to change his campaign, because he decided to become a sub.. I say keep it how it is and let the dust settle