* Payne knows Olympic benefits as Atlanta chief * Not everyone excited about golf's Olympic return (Adds quotes, detail, byline) By Steve Keating AUGUSTA, Georgia, April 4 (Reuters) - Golf's major championships threw their support behind the sport's return to the Olympics on Monday, offering exemptions for men's and women's gold medal winners this year to all grand slam events. Augusta National chairman Billy Payne, who ran the 1996 Atlanta Games, told a news conference that the men's gold medal winner in Rio de Janeiro, where golf will make its return to the Summer Games for the first time in more than a century, would get an invitation to the 2017 Masters. The Royal and Ancient and Ladies Golf Union will offer similar one-year exemptions to the men's and women's British Opens while the PGA of America and United States Golf Association followed suit with their two flagship events. More...