because it gets you off the hook.
people who think the world is coming to an end and jesus is coming back don't have any reason to make things better. if you truly expect the world to end any minute - or even within a generation - why waste the time and energy? if you don't see any long term future, how can you be expected to have a stake in it?
since it's clear to me that these kinds of beliefs can lead to such short-sighted, narrow-minded world views such as those espoused by Phlegm Fleck, it's equally clear (to me at least) that these beliefs are better off consigned to the dust-heap of history. because these beliefs mostly evoke fear, this becomes a path easily manipulated by those false prophets jesus himself warned about - especially if you lack the critical and analytical thinking skills that used to be encouraged in education.
or, in the alternative, we can always hope they'll be raptured out of existence.
and furthermore, the war will end. blessed be.