Secret Sauce wrote
It's tough to say how much a player's preference influences a player's decision. For example, I doubt A.J. Burnett "preferred" Toronto to St. Louis in the off-season before 2006. He said he was interested in St. Louis and grew up in Alabama a Cardinal fan, but money talks sometimes. I'm sure it's different for every player, but it's probably the best idea to just take this kind of info with a grain of salt.
And when Burnett was a free agent before the 2006 season, when speaking with the Chicago media he denied he was ever a Cardinal fan and proclaimed that when he was growing up in Arkansas, he and his whole family were Cubs fans because they got all of Chicago's games on cable, on WGN.
Where a pro athlete grew up and which team he was a fan of as a kid are probably the least important considerations in the subject of free agency.