I think it comes down to basic survival instinct and preservation of life as sacred. They have done a somewhat good job at getting humanity pretty far in the whole natural selection thing, but now, as we evolve, life is less pleasing and maybe even less significant, even though that thought despises me. We get to live a lot longer than nature would allow us, do a lot more than any animals should, just in a general sense we are not really animals in any sense other than our need to feed and have sex (and even those are becoming more and more dislikeable). Still, people who want to live, and society as a whole, see death as "losing the game", and that is so scary that they try to push any sign of it away, even if it's not their own death. Which I think is really disrespectful and not empathic at all.