I personally support raising the minimum wage, so I believe Wal-Mart should set the standard by increasing wages for their employees. Seeing as how they currently hire most people who apply, raising wages would increase interest in their company, resulting in a larger group of potential employees to pull from, thus improving the quality of new hires rather than simply the quality.
The Walton family who own and control Wal-Mart are one of the wealthiest in the country and world. However, their stores are often built on the back of publicly funded infrastructure and their employees are paid such low wages that many are often forced to enroll in public welfare programs such as food stamps. Wal-Mart is notorious for treating their employees badly, while the public supports the Walton families ever growing wealth.
Typically, jobs like those at Wal-Mart are not meant to be careers or a lifelong job. These types of jobs are meant for young high school graduates or older retired people. Working in a retail establishment should not be encouraged and should be used as a means of earning money to better oneself. These types of jobs should be considered stepping stones, so wage increases should not be given. Paying people more for these jobs encourages them to stay where they are at and not try to create a better life for themselves.
Wal-Mart is like any other employer, and should offer wages that are competitive enough to get good employees, but not so much more that they lose profits, which would jeopardize their business (and ability to hire additional workers). The fact that Wal-Mart is larger than some other employers does not mean they don't need to compete. Also, if they artificially inflate salaries, it would harm other local businesses who could not compete and would lose their employees.