A Sort-Of Answer

I think I have a sort of answer:  

•    It is hard to care. Because if we genuinely care, we feel the need or moral obligation to do something about it.  
•  It is hard to change long-held opinions. To accept or even just listen to irrefutable evidence that is contrary to what we have always blindly believed is incredibly hard. For example, we were taught from day one that this is black and this is white, but suppose your parents and your teachers taught you that black was yellow, and then when you finally get out into the world, and people tell you that it is actually black, of course you will straight away think that everyone is loopy, because you were brought up to believe that it is yellow. Sorry about this terrible analogy, but do you get what I’m saying??? Eventually you will have to realise that your parents mislead you.  It’s just like it was hard for me to figure out why I really was a Christian, that I wasn’t just believing  everything my parents spoon-fed me since birth. The apostle Paul tells us to test everything (1Thes 5:21), and that is what we should do most importantly with our faith, but also with every other opinion that we have as well.  It frustrates me to no end when people instantly dismiss and ignore you simple because you have some evidence that is contrary to what they have been taught by their parents or the media. 
•  Ignorance is bliss. As we gradually come to the realisation that life is not the wonderful place in which corruption does not exist, it sucks. We were much happier with ignorance. But ignorance does not change that the problem still exists. Being ignorant only makes it worse for our children and the generations after us.  There is a lot more I could say, but these are the main reasons I think.