In Mendenhall's defense all the rookies who join the league are concentrated from their hometowns into one location where they go through the combine. At the combine they are poked and prodded by their wealthy bosses to see which are the biggest, strongest and fastest. The strong are purchased while the weak are discarded. Players have no say in where they choose to work and are instead told where they are to live and what work they will do.
I am not saying that the NFL is slavery I am just saying a person could draw a parallel. If you don't know what that means go look up the word "parallel."
Thank God for "NFL slavery." Could you imagine the NFL if it were like the NBA and players could join whatever team they wanted at any time? How terrible would it be if Megatron, AD, Gronk, and Fitz pulled a LeBron and decided they were going to go join their bestest friend A-Rod in GB.