In short, such animals are being treated as a thing not as a being.
yes, most of the time but animal rights activists are trying to change that because they are not 'thing's but living beings that feel and suffer. and yes, they are being decieved as humans take advantage of their weaknesses and their blindspots (unaware they are being used or exploited as in motive) in comparison to us.
if you want to blame something, blame the universe, because ultimately that's the way it runs here (predatorial). i don't agree with it myself as this place is like a nightmare you woke up to if you have any ethics at all.