He's been described as a big family guy, and in all honesty, I'd rather live in Phoenix than I would MN.
I know we view these guys as mercenaries, but being around family and a place you're able to enjoy year-round (as opposed to deathly cold, snowy winters), is a factor for a wife and kids and such, especially for a guy who has already put as much in the bank as Kirk. (Trust me guys, I'm trying to figure out all of the possible reasons he can come here because I want him to be a Cardinal so much, I know I'm reaching some.)