Is it me only or do you guys actually realised, all the cutscenes used the in-game materials instead of CG? Are they facing economical problem to make a good and pretty CG for those cutscenes?

Other blizzard franchise also make CG for the cutscenes, but what happen to WoW? It started when WotLK release it's 2nd trailer, the first trailer where Lich King came out, the CG is very good, but 2nd trailer is zzz.