User blog comment:Sannse/Checking in and catching up/@comment-25181282-20130506220235/@comment-5884303-20130506220557

Because Wikia isn't a place to spam advertisements. For example if at Brickimedia, a wiki wanted to move off and go to Wikia, we wouldn't allow their Brickimedia wiki to be turned into a pointless spam site with advertisements to Wikia all over it.