I guess it also reflects general Chinese attitude towards religion and faith. When I read Western novels that touch upon religion, usually there is a sense of higher power at work or deep belief in respective god(s) - enough to cause a war. In JY world, nearly all characters with speaking parts became monks, nuns, taoists due to sour relationships, death, or practicing higher level of MA or obtaining rare manuals; or eccentric people hiding from "real" world.
Even naive old monk Cheng seem to have fell into the Buddhism business because he was an orphan brought up by the monastery.
Just an observation. However, there seems to be heavy influence in the belief of karma and perhaps reincarnation in the undertones.