Ritual killing of chickens....Kapparot

[Catherine]

Every year Orthodox Jews kill chickens as an act of atonement in a practice called Kapparot.
There is a certain amount of violence and abuse in the killing and afterwards the meat is thrown away. It isn't even used as food. It is treated as garbage.             

http://www.laweekly.com/news/ultra-orhto...ay-8725261

This is what happens every year.

I am not criticizing any particular religion. I am just mentioning this particular ritual animal killing because it is current and we are all familiar with it. It is important that we keep protesting this event because so many chickens are killed so badly.

The real thought that I have is, why is any religion still killing animals? No matter what our roots and what our practices are we should have grown way past ritual animal killings. This is the 21st century. We have grown sensitive to so many things that we never considered before. Ritual animal killing is something very primitive that has been part of the human past. Shouldn't we be leaving it in the past. 

If we have grown up in so many ways, why do we still hold on to this primitive taking of life? 
How can abusing a chicken or any other animal be an act of atonement?