I'm a little late in reading this thread, so here goes. One of the reasons Nicklaus did not spend as much time with his family . . .
Actually, I think we may be a bit offbase here.
As tball88 stated above, Lee Trevino was the guy who sacrificed everything for golf. He was driven to escape the poverty and prejudice of his youth:
"I put golf before my family. I put it before my friends. I put it before my religion."
Jack Nicklaus sacrificed none of these. Instead, he rarely played more than twenty tournaments a year and made a great deal of time for his family. He was there for his wife and children -- he literally fainted dead away after the birth of each child -- throughout the important events of their lives, sometimes even jetting home during tournaments.
In fact, his commitment to 'family time' inspired Chi Chi Rodriquez's great line:
"Jack Nicklaus became a legend in his spare time."