He's probably looked at it and felt that it wasn't as important in terms of the best ROI for his foundation. His foundation takes a very analytical approach an

He's probably looked at it and felt that it wasn't as important in terms of the best ROI for his foundation. His foundation takes a very analytical approach and he wouldn't dismiss that issue lightly. They can't tackle everything. You have to pick your battles, even when you're the richest man in the world.