Now imagine for a moment that you are one of the parents attending the funeral of your recently murdered child. You are experiencing the worst pain and grief that you could ever imagine. You wonder how you will be able to continuing living in the wake of such horror and despair. This is as bad as life gets.
Now imagine a crowd of belligerent, hate-mongering assholes off to the side chanting and holding signs displaying slogans such as "Thank God for Killing Your Child!" and "Your Child is in Hell! Praise the Lord!".
Now ask yourself, would you ignore that? Could you ignore that?
If your answer is "no" as I imagine would be the case for most people, then perhaps we need to do more than just "ignore them".
I once prayed to god for a bike, but quickly found out he didnt work that way...so I stole a bike and prayed for his forgiveness.