Also, every major religion uses the threat of eternal punishment in hell to scare people into behaving. Fear has never worked, whether it was temporary pain or when it was accepted to be eternal torment.
No, that whole afterlife thing is mainly just the death cults. Christianity, Islam, and several others in history.
But Jews and Buddhists for example don't really have afterlife-centric beliefs. If you ask a rabbi, he'll tell you "souls come from God and they return to God." And there's not really even so much as speculation about whether there is an experiential afterlife and whether it is filled with suffering or glory.
If you ask a Buddhist, then depending on what path of Buddhist, he'll either tell you the question is irrelevant, or tell you that we are to be reincarnated until we have no more to learn - and there isn't much in the way of any belief about what happens after that point; "Nirvana" is a concept, not a place anyone expects to experience. What they expect to experience on achieving Nirvana - is Nothing. Pure oblivion, a complete cessation of experience. And there are lots of variations on that belief throughout the Eastern hemisphere.
These are MAJOR religions, with millions, and sometimes billions, of followers. They just happen not to be the kind of death cults that drive this sort of violence.