People believe that justice prevails because the belief is in the interest of unjust rulers, and they have the power to make people think this. Think about, for instance, what happens when a business owner always has to look over his shoulder to ensure that employees are not stealing from him. Thievery complicates this owner's life. It is in his best interests to exploit his workers as much as possible, and he will do this to the best of his ability. But, on the other hand, he wants his workers to fully denounce notions like thievery or exploitation. Otherwise, they may try to compete with the owner! Because the owner owns stuff and is in charge, it is within his power to teach his workers not to steal.
Overtime, workers are successful because they do what the owner wants and he allows them to live. And the owner is successful because all the workers are doing things for him. He continues to be secretly evil meanwhile his workers never try to compete with him. This is how things really work.
Christianity is basically a religion that emerged thousands of years ago in protest of things working this way. However, the message of that religion was wrong. Instead of teaching workers to stand up for their own interests, it taught them to be better slaves in the hopes that they will go to fairy land when they die. I may be the first to tell you this, and if so, I hope that you learn from it. Fighting for fairness might be what Jesus wants, but that's not how you win. You should always be trying to win. So unless justice is directly in your interests and you think you can actually change things, stop fighting for it. Be evil instead. Because injustice prevails.