I remember when the Magic man dropped the bomb in 1991 about his HIV status. There was a lot of stories regarding sex, athletes and marriage. I remember thinking - "I wonder how many will keep it in their pants now?" Apparently that news is too far in the past to scare anyone any more.
Personally, I am surprised that so many athletes hook up with groupies. Not because they can, but because of the potential problems. HIV, STDs, bastard children, etc... are just a few of the unintended consequences, not to mention public image, children that hate their father for embarrassing their mother, and in some cases ruining other relationships.
Good for Grant and others that use a bit of self control.
Like someone else said, if you want to be single, unattached to anything or hamstrung by moral values - then don't attach yourself to a wife and children.