My first reaction is simple, it certainly seems worse to kill someone than to hire them at minimum wage. But let's take a closer look.
1. What Does the Social Magisterium of the Church Tell Us?
Our Holy Father's, since the advent of the Industrial Revolution, have spoken forcibly against the increasing exploitation of the poor by the rich. This teaching was launched by the great Pope Leo XIII with his masterful encyclical Rerum Novarum. The Church teaches us that we can never sit idly by and allow the weak, poor, infirm, unborn, or otherwise oppressed to fend for themselves. No one, within the bounds of Catholic teaching and thought, advocates a "pull yourself up by your bootstraps" mentality where we, like Cain, declare "am I my brother's keeper?" The call to aid the poor, however, cannot be conflated with denouncing that some are rich and others are poor. The Gospel cannot be confused with irradiating world poverty for such isn't the first concern of the Church.
2. What is the Church's Primary Concern?
The primary concern of the Holy Catholic Church is, and must always be, the salvation of immortal souls and can never be the temporal enrichment of the poor. The Church, as Pope Francis has pointed out, is not another NGO. It isn't primarily occupied with enriching the poor and it is even less occupied with taking from the rich to give to the poor. We are followers of Christ Jesus, not of Robin Hood. That doesn't mean the Church has no concern for the temporal wellbeing of Catholics or of the poor. She does. The Church, as evidenced by encyclicals like Rerum Novarum and in her perennial call to the "works of mercy" including "feeding the hungry," "sheltering the homeless," and "clothing the naked," cares deeply about both the body and the soul of each person. We wouldn't want to fall into a Gnosticism that holds that the body is unimportant, while the "spirit" is all that matters. However, we will also note that the corporal works of mercy include sharing with the poor but mentions nothing about taking away (and certainly not by force of the State) anything from the rich. Catholicism rather calls on individuals to practice charity and almsgiving as virtues than it calls for a high tax rate to strip people of wealth and "redistribute" it.
3. What About the Sixth and Tenth Commandments?
The advocacy of wealth redistribution runs into yet more problems when we look to God's abiding moral law - the Ten Commandments. We read, in the Sixth Commandment, "Thou shall not steal." What is taking, by force of the State, from some to give to others but stealing? Certainly, we can see the fairness of allowing the proper authorities tax citizens. Jesus Himself approves of this by establishing the principle "render unto Caesar that which is Caesar's and to God that which is God's" in the context of questions over Roman taxation of the Israelites. However, taxation can become unjust when it seeks not to simply provide for the State but seeks to steal from citizens to give money to a privileged group. Worse still, the advocate of wealth redistribution, in looking at someone like Bill Gates and demanding his money be given to those less wealthy, seems to be immediately trespassing the Tenth Commandment - "thou shall not covet thy neighbor's goods." If we are seeking not just to pull people out of poverty, but to create and equal distribution of wealth then we certainly seem to be coveting. On top of this, we seem to have also run afoul of the Deadly Sin of Envy. The redistributionist isn't just jealous of his neighbor's wealth - i.e. he doesn't just want to become wealthy himself - he envies his neighbor's wealth - i.e. he wants his neighbor to be poorer. All of this runs clearly against the grain of the Gospel which seeks to free us from being overly concerned with money and to be more concerned with holiness.
4. What Would Jesus Say?
Jesus Himself best exemplifies what is wrong with the attitude of a redistributionist. He tells us that hoarding wealth can be fatal to the soul (see the parable of the rich man and Lazarus in Luke 16 and the parable of the rich fool in Luke 12). Jesus goes on to tell us, "it is easier for a camel to go through the eye of a needle than for someone who is rich to enter the Kingdom of God." (Matt 19:24). More directly, He says, "take heed and beware of all covetousness; for a man's life does not consist in the abundance of his possessions" (Lk 12:15). Jesus warns us against wanting to acquire wealth, not against an unequal distribution of wealth (which the Gospel takes for granted, hence the call for almsgiving, which would be impossible without some have more than others).
5. What Did Mother Teresa Say?
Perhaps no saint in modern times, and maybe even no saint, save for Francis of Assisi, in the entire history of the Church, better exemplifies the Church's commitment to the poor than Blessed Teresa of Calcutta, known the world over simply as Mother Teresa. She, who lived among the poorest of the poor, among people so poor as to make the "poor" in a country like the United States seem wealthy, decried not "income inequality" but abortion as "the greatest destroyer of peace today." She realized that killing someone is always worse than taking possession from them, or even from hoarding wealth. Over sixty million babies have been brutally murdered at the hands of American abortionists in the last half century and Mother Teresa, who we might expect to be especially concerned with American wealth when compared to Indian poverty, pointed to precisely this evil (abortion) as the primary evil facing the world.
It is noble to want to help the poor. More than that, it is necessary for every true Christian. We can never sit back and amass possessions while being indifferent to the plight of the poor and the oppressed. However, as we've seen above, this righteous instinct can be used by the Father of Lies to warp our understanding of the Faith into something covetous, envious, greedy, and evil. There is no one better at twisting what ought to be righteousness into evil and sin than Satan. Almsgiving, and even encouraging the super-wealthy (the "1%") to share, are Christian ways of living the Gospel. Calling for the State to redistribute the wealth, calling for "wealth equality," is a perversion of the Gospel. All of which is why St. Josemaría Escrivá can say,
Don't you think that equality, as many people understand it, is synonymous with injustice? (The Way, 46).