Earl Thomas as of this writing is a Seattle Seahawk on the eve of the NFL draft. There have been plenty of rumors that Thomas will be traded to the Dallas Cowboys or some other team. The Cowboys come up a lot for one reason.
Earl Thomas on visiting Cowboys locker room after game: When the Seahawks kick me to the curb, please, Cowboys, come get me pic.twitter.com/gqp0eb2VFo
Thomas is from Texas and grew up as a Cowboys fan. But there are plenty of current NFL players who probably grew up as fans of different teams than they ones they play for.