Pool cue is more expensive than snooker cue as it could be made up by alot more types of different wood ( old wood ) and designs . I`ve seen pool cues which cost up to $ 20000 US .
On average basis, a snooker fanatic might well spend 200 - 450 sterling pound for a nice snooker cue. But for a pool crazy, he/she might spend 500 - 2000 sterling pound for his/her piece of equipment for his/her game. (There are more expensive collectors' pool cue of course.)
The reason behind the high price is because of the craftsmanship. Good pool cue maker can make a cue that people view it as a piece of art.