Some people are convinced of the whole survival of the fittest theory. And some are just greedy for all life has to offer. Death is after all the end of life's pleasures and you have people rushing to grab em all while they can.
When you really stop to ponder you start realizing how pointless all this covetousness is when you have to leave em all behind. Non of this is gonna benefit you or avail you when you are six feet under and covered in sand!