Even PSG have sold players this summer (like Gameiro for instance). I don't think they nor Monaco will be buying any more, Barca can only really justify getting a defender, Citeh have already spent near £100 million, Real Madrid are tied up with getting Bale for whatever ludicrous sum it will end up being and Chelsea are trying to get Rooney.
It's about us and Man Utd who have done minimum business out of those that seemingly have a lot to be able to spend.