In a normal job, you don't (shouldn't) witness this kind of behavior.
But professional football IS NOT a normal job. In no other job a recent hired professional with no experience whatsoever in the market gets a starting salary that tops the veterans. In no other job if you get injuried and your contract is coming up, you get releases/not signed.
So let's not confuse pro football with any other job. The values are more of the military than of a civilian environment.
Like Wolvi said, there's a line in hazing, but that was nowhere near it.
Of course, the Cowboys could've been more dilligent and have made Dez carry Miles Austin's pads instead of Roy williams...