Why are Republicans against workers right? Why are they fighting for these massive Corporations against Unions?

One thing I really have a hard time understanding, is how these Corporations get sympathy from Republicans / Tea parties. The Tax Rate on the Top earners in this country are at the lowest point in 60 years. Corporations are sitting on Trillions of dollars and not improving worker rights, or worker pay. Take Wal-Mart for example. Currently the average full time walmart employee makes $8.23 per hour, or $13,861 a year, while the federal poverty line for a family of three was $14,630. Democrats brought a Lawsuit against Walmart back in 2006, which was shot down by republicans, because walmart management was encouraging their employee's to seek Welfare and Medicaid Benefits. Walmart gets nearly 2 Billion dollars a year in United states Subsidies from the FED. And 10% of their workforce is on govt assistance. Unions have been fighting with walmart since 2000 trying to get them to raise Pay so their employees and their families do not live off the govt and can provide for their families. Walmart has the Power and Money to make this happen, yet with help from Republicans, they are able to keep winning the battle. Look at the amount they receive in Subsidies, 2 billion a year, look at the amount it cost the govt to provide federal assistance to their employees. The company did nearly half a Trillion dollars in Sales for 2010.. Profit nearly 200 Billion dollars in 1 year alone.. They Employ about 1 Million people. And the Average employee makes 14.6k a year. So 1 Million times 14.6k is 14.6 Billion dollars. The company is walking away with 87% Of the profit LOL what business do you know can make 87% of the Profit as take home? Even if it's 80%. Would you work for a company? That only paid it's employees 13% of the profits? Divided among all employees?