Most people just don't care enough to do anything about injustice, or don't think about it at all. It's infuriating to see how apathetic and irresponsible people can be. Just look at the meat industry. People could stop, but they don't. They only care that their virtue is signalled and that the suffering is far enough detached and out of sight so that they don't have to face it and actually self-reflect on their cognitive dissonance or flaws. What's worse is that eating meat is often culturally engrained, and so similar to religious indoctrination, even harder to quit. All this, done by years of lobbying of the meat industry and other unethical practices. These problems of injustice are deep-rooted in our society, and entitlement/lack of empathy. The arguments used for factory farming these days are the same slavers used in the past, and even now it is just transferred elsewhere so that people can be exploited all for a cheaper product to consume.

Things get even sadder when you realise that all the injustice in the world is for nothing but ego or extreme selfishness. I honestly think it's a large reason people still believe in religion. When you face the injustice in the world and become aware of it, you either have to ignore it/find a way to cope or actually do something. As long as people remain ignorant, uneducated and don't have empathy for others, this will continue.