Oh come -can't do anything about it??? You must be joking!!! I bet they would have done something about it if the squatters had put themselves into a C seat very quickly. Hey you are issued boarding cards for a reason and if you have a boarding card then the seat is yours - allocated by the airline and held as such in the manifest.
This may sound nasty but that is the reason some times the wrong bodies ended up in the wrong place (prior to DNA times) The straped in bodies were ID'ed via seat number assuming the seat issued was also the one you were supposed to be in. Remember the serviette found in the seat pocket with apparently the big "B" word. Well guess who the go looking for - yes the person holding the boarding pass for THAT seat and not for the "squwatters" because according to the manifest they are sitting elsewhere!!!
This is however not the first time Emirates has shown a lack of common sence. Remember the the passenger who bought a C class ticket and ended up fly eco because someone with the same name checked into his seat and Emirates did nothing to check who really purchased the seat and who was really on board the flight. In the end it apparently turned out to be a case of internal fraud but not very comforting to know god know who can get on the plane and even when discovered on the ground nothing is done to secure who really is onboard.