Why? It's silly to ask that question, especially in a professional environment. Wal-Mart, no matter how low rent, is still a professional environment, so it should be treated as such by all employees. This means using your real name on the name tag you're given.
As far as I can tell it's because of how much post-processing is on any of their songs.
Though, that very same argument can be applied to such trite as Akon and Justin Bieber and people still like them, so that argument falls apart.
Two Steps From Hell - Invincible