Although Rusty Hardin and his firm do practice criminal defense, Rusty Hardin himself has primarily practiced civil litigation for the past couple of years. Civil litigation is quite a bit different than criminal defense, particularly as it comes to Discovery. In this particular case, I would imagine that Rusty's criminal defense experience is an added bonus.
Regarding Buzbee, he's also representing the family of a Conroe girl who froze to death due during recent cold weather. I agree that he wouldnt necessarily be representing these individuals for fame/money. At the end of the day that's why we have trials.